Displaying 1-10 of 23 results found.
Triangle read by rows: T(n,k) = t(n-k, k); t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), where f(x) = 3*x + 2.
+10
14
1, 2, 2, 4, 20, 4, 8, 132, 132, 8, 16, 748, 2112, 748, 16, 32, 3964, 25124, 25124, 3964, 32, 64, 20364, 256488, 552728, 256488, 20364, 64, 128, 103100, 2398092, 9670840, 9670840, 2398092, 103100, 128, 256, 518444, 21246736, 147146804, 270783520, 147146804, 21246736, 518444, 256
FORMULA
T(n,k) = t(n-k, k); t(0,0) = 1, t(n,m) = 0 if n < 0 or m < 0, else t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), where f(x) = 3*x + 2.
T(n, k) = (a*k + b)*T(n-1, k) + (a*(n-k) + b)*T(n-1, k-1), with T(n, 0) = 1, a = 3, and b = 2. - G. C. Greubel, Mar 20 2022
EXAMPLE
Triangle begins as:
1;
2, 2;
4, 20, 4;
8, 132, 132, 8;
16, 748, 2112, 748, 16;
32, 3964, 25124, 25124, 3964, 32;
64, 20364, 256488, 552728, 256488, 20364, 64;
128, 103100, 2398092, 9670840, 9670840, 2398092, 103100, 128;
256, 518444, 21246736, 147146804, 270783520, 147146804, 21246736, 518444, 256;
MATHEMATICA
T[n_, k_, a_, b_]:= T[n, k, a, b]= If[k<0 || k>n, 0, If[n==0, 1, (a*(n-k)+b)*T[n-1, k-1, a, b] + (a*k+b)*T[n-1, k, a, b]]];
Table[T[n, k, 3, 2], {n, 0, 12}, {k, 0, n}]//Flatten (* G. C. Greubel, Mar 20 2022 *)
PROG
(Sage)
if (k<0 or k>n): return 0
elif (n==0): return 1
else: return (a*k+b)*T(n-1, k, a, b) + (a*(n-k)+b)*T(n-1, k-1, a, b)
flatten([[T(n, k, 3, 2) for k in (0..n)] for n in (0..12)]) # G. C. Greubel, Mar 20 2022
CROSSREFS
See similar sequences listed in A256890.
Triangle read by rows: T(n,k) = t(n-k, k); t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), where f(x) = 2*x + 2.
+10
13
1, 2, 2, 4, 16, 4, 8, 88, 88, 8, 16, 416, 1056, 416, 16, 32, 1824, 9664, 9664, 1824, 32, 64, 7680, 76224, 154624, 76224, 7680, 64, 128, 31616, 549504, 1999232, 1999232, 549504, 31616, 128, 256, 128512, 3739648, 22587904, 39984640, 22587904, 3739648, 128512, 256
FORMULA
T(n,k) = t(n-k, k); t(0,0) = 1, t(n,m) = 0 if n < 0 or m < 0, else t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), where f(x) = 2*x + 2.
T(n, k) = (a*k + b)*T(n-1, k) + (a*(n-k) + b)*T(n-1, k-1), with T(n, 0) = 1, a = 2, and b = 2.
T(n, n-k) = T(n, k).
EXAMPLE
Triangle begins as:
1;
2, 2;
4, 16, 4;
8, 88, 88, 8;
16, 416, 1056, 416, 16;
32, 1824, 9664, 9664, 1824, 32;
64, 7680, 76224, 154624, 76224, 7680, 64;
128, 31616, 549504, 1999232, 1999232, 549504, 31616, 128;
256, 128512, 3739648, 22587904, 39984640, 22587904, 3739648, 128512, 256;
MATHEMATICA
T[n_, k_, a_, b_]:= T[n, k, a, b]= If[k<0 || k>n, 0, If[n==0, 1, (a*(n-k)+b)*T[n-1, k-1, a, b] + (a*k+b)*T[n-1, k, a, b]]];
Table[T[n, k, 2, 2], {n, 0, 12}, {k, 0, n}]//Flatten (* G. C. Greubel, Mar 21 2022 *)
PROG
(Magma)
function T(n, k, a, b)
if k lt 0 or k gt n then return 0;
elif k eq 0 or k eq n then return 1;
else return (a*k+b)*T(n-1, k, a, b) + (a*(n-k)+b)*T(n-1, k-1, a, b);
end if; return T;
end function;
[T(n, k, 2, 2): k in [0..n], n in [0..12]]; // G. C. Greubel, Mar 21 2022
(Sage)
if (k<0 or k>n): return 0
elif (n==0): return 1
else: return (a*k+b)*T(n-1, k, a, b) + (a*(n-k)+b)*T(n-1, k-1, a, b)
flatten([[T(n, k, 2, 2) for k in (0..n)] for n in (0..12)]) # G. C. Greubel, Mar 21 2022
CROSSREFS
Cf. similar sequences listed in A256890.
Triangle read by rows: T(n, k) = t(n-k, k), where t(0,0) = 1, t(n,m) = 0 if n < 0 or m < 0, else t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), and f(n) = 3*n + 3.
+10
12
1, 3, 3, 9, 36, 9, 27, 297, 297, 27, 81, 2106, 5346, 2106, 81, 243, 13851, 73386, 73386, 13851, 243, 729, 87480, 868239, 1761264, 868239, 87480, 729, 2187, 540189, 9388791, 34158753, 34158753, 9388791, 540189, 2187, 6561, 3293622, 95843088, 578903274, 1024762590, 578903274, 95843088, 3293622, 6561
FORMULA
T(n, k) = t(n-k, k), where t(0,0) = 1, t(n,m) = 0 if n < 0 or m < 0, else t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), and f(n) = 3*n + 3.
t(k, n) = t(n, k).
T(n, n-k) = T(n, k).
t(0, n) = T(n, 0) = A000244(n). (End)
EXAMPLE
Array t(n,k) begins as:
1, 3, 9, 27, 81, 243, ...;
3, 36, 297, 2106, 13851, 87480, ...;
9, 297, 5346, 73386, 868239, 9388791, ...;
27, 2106, 73386, 1761264, 34158753, 578903274, ...;
81, 13851, 868239, 34158753, 1024762590, 25791697782, ...;
243, 87480, 9388791, 578903274, 25791697782, 928501120152, ...;
729, 540189, 95843088, 8959544136, 575025893586, 28788563928042, ...;
Triangle T(n,k) begins as:
1;
3, 3;
9, 36, 9;
27, 297, 297, 27;
81, 2106, 5346, 2106, 81;
243, 13851, 73386, 73386, 13851, 243;
729, 87480, 868239, 1761264, 868239, 87480, 729;
2187, 540189, 9388791, 34158753, 34158753, 9388791, 540189, 2187;
MATHEMATICA
t[n_, k_, p_, q_]:= t[n, k, p, q] = If[n<0 || k<0, 0, If[n==0 && k==0, 1, (p*k+q)*t[n-1, k, p, q] + (p*n+q)*t[n, k-1, p, q]]];
T[n_, k_, p_, q_]= t[n-k, k, p, q];
Table[T[n, k, 3, 3], {n, 0, 12}, {k, 0, n}]//Flatten (* G. C. Greubel, Feb 28 2022 *)
PROG
(Sage)
@CachedFunction
def t(n, k, p, q):
if (n<0 or k<0): return 0
elif (n==0 and k==0): return 1
else: return (p*k+q)*t(n-1, k, p, q) + (p*n+q)*t(n, k-1, p, q)
def A257620(n, k): return t(n-k, k, 3, 3)
CROSSREFS
Similar sequences listed in A256890.
Triangle, read by rows, T(n,k) = t(n-k, k) where t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1) and f(n) = 2*n + 3.
+10
11
1, 3, 3, 9, 30, 9, 27, 213, 213, 27, 81, 1308, 2982, 1308, 81, 243, 7431, 32646, 32646, 7431, 243, 729, 40314, 310263, 587628, 310263, 40314, 729, 2187, 212505, 2695923, 8701545, 8701545, 2695923, 212505, 2187, 6561, 1099704, 22059036, 113360904, 191433990, 113360904, 22059036, 1099704, 6561
FORMULA
T(n, k) = t(n-k, k), where t(0,0) = 1, t(n,m) = 0 if n < 0 or m < 0, else t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), and f(n) = 2*n + 3.
t(k, n) = t(n, k).
T(n, n-k) = T(n, k).
t(0, n) = T(n, 0) = A000244(n). (End)
EXAMPLE
Array t(n,k) begins as:
1, 3, 9, 27, 81, 243, ...;
3, 30, 213, 1308, 7431, 40314, ...;
9, 213, 2982, 32646, 310263, 2695923, ...;
27, 1308, 32646, 587628, 8701545, 113360904, ...;
81, 7431, 310263, 8701545, 191433990, 3579465642, ...;
243, 40314, 2695923, 113360904, 3579465642, 93066106692, ...;
729, 212505, 22059036, 1351133676, 59641127202, 2104476295026, ...;
Triangle T(n,k) begins as:
1;
3, 3;
9, 30, 9;
27, 213, 213, 27;
81, 1308, 2982, 1308, 81;
243, 7431, 32646, 32646, 7431, 243;
729, 40314, 310263, 587628, 310263, 40314, 729;
2187, 212505, 2695923, 8701545, 8701545, 2695923, 212505, 2187;
MATHEMATICA
t[n_, k_, p_, q_]:= t[n, k, p, q] = If[n<0 || k<0, 0, If[n==0 && k==0, 1, (p*k+q)*t[n-1, k, p, q] + (p*n+q)*t[n, k-1, p, q]]];
T[n_, k_, p_, q_]= t[n-k, k, p, q];
Table[T[n, k, 2, 3], {n, 0, 12}, {k, 0, n}]//Flatten (* G. C. Greubel, Feb 28 2022 *)
PROG
(PARI) f(x) = 2*x + 3;
T(n, k) = t(n-k, k);
t(n, m) = if (!n && !m, 1, if (n < 0 || m < 0, 0, f(m)*t(n-1, m) + f(n)*t(n, m-1)));
tabl(nn) = for (n=0, nn, for (k=0, n, print1(T(n, k), ", "); ); print(); ); \\ Michel Marcus, May 06 2015
(Sage)
@CachedFunction
def t(n, k, p, q):
if (n<0 or k<0): return 0
elif (n==0 and k==0): return 1
else: return (p*k+q)*t(n-1, k, p, q) + (p*n+q)*t(n, k-1, p, q)
def A257611(n, k): return t(n-k, k, 2, 3)
CROSSREFS
Similar sequences listed in A256890.
Triangle, read by rows, T(n,k) = t(n-k, k) where t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), and f(x) = x + 3.
+10
10
1, 3, 3, 9, 24, 9, 27, 141, 141, 27, 81, 726, 1410, 726, 81, 243, 3471, 11406, 11406, 3471, 243, 729, 15828, 81327, 136872, 81327, 15828, 729, 2187, 69873, 533259, 1390521, 1390521, 533259, 69873, 2187, 6561, 301362, 3295152, 12609198, 19467294, 12609198, 3295152, 301362, 6561, 19683, 1277619, 19489380, 105311556, 237144642, 237144642, 105311556, 19489380, 1277619, 19683
FORMULA
T(n,k) = t(n-k, k), where t(0,0) = 1, t(n,m) = 0 if n < 0 or m < 0, else t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), and f(x) = x + 3.
Sum_{k=0..n} T(n, k) = A001725(n+5).
t(k, n) = t(n, k).
T(n, n-k) = T(n, k).
t(0, n) = T(n, 0) = A000244(n). (End)
EXAMPLE
Array t(n,k) begins as:
3, 24, 141, 726, 3471, 15828, ...;
9, 141, 1410, 11406, 81327, 533259, ...;
27, 726, 11406, 136872, 1390521, 12609198, ...;
81, 3471, 81327, 1390521, 19467294, 237144642, ...;
243, 15828, 533259, 12609198, 237144642, 3794314272, ...;
729, 69873, 3295152, 105311556, 2607816498, 53824862658, ...;
Triangle T(n,k) begins as:
1;
3, 3;
9, 24, 9;
27, 141, 141, 27;
81, 726, 1410, 726, 81;
243, 3471, 11406, 11406, 3471, 243;
729, 15828, 81327, 136872, 81327, 15828, 729;
2187, 69873, 533259, 1390521, 1390521, 533259, 69873, 2187;
6561, 301362, 3295152, 12609198, 19467294, 12609198, 3295152, 301362, 6561;
MATHEMATICA
f[n_]:= n+3;
t[n_, k_]:= t[n, k]= If[n<0 || k<0, 0, If[n==0 && k==0, 1, f[k]*t[n-1, k] +f[n]*t[n, k-1]]];
T[n_, k_]= t[n-k, k];
Table[T[n, k], {n, 0, 12}, {k, 0, n}]//Flatten (* G. C. Greubel, Feb 22 2022 *)
PROG
(PARI) f(x) = x + 3;
T(n, k) = t(n-k, k);
t(n, m) = {if (!n && !m, return(1)); if (n < 0 || m < 0, return (0)); f(m)*t(n-1, m) + f(n)*t(n, m-1); }
tabl(nn) = {for (n=0, nn, for (k=0, n, print1(T(n, k), ", "); ); print(); ); } \\ Michel Marcus, Apr 23 2015
(Sage)
def f(n): return n+3
@CachedFunction
def t(n, k):
if (n<0 or k<0): return 0
elif (n==0 and k==0): return 1
else: return f(k)*t(n-1, k) + f(n)*t(n, k-1)
def A257627(n, k): return t(n-k, k)
CROSSREFS
Similar sequences listed in A256890.
Triangle read by rows: T(n,k) = t(n-k, k); t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), where f(x) = 4*x + 2.
+10
10
1, 2, 2, 4, 24, 4, 8, 184, 184, 8, 16, 1216, 3680, 1216, 16, 32, 7584, 53824, 53824, 7584, 32, 64, 46208, 674752, 1507072, 674752, 46208, 64, 128, 278912, 7764096, 33244544, 33244544, 7764096, 278912, 128, 256, 1677312, 84892672, 636233728, 1196803584, 636233728, 84892672, 1677312, 256
COMMENTS
Corresponding entries in this triangle and in A060187 differ only by powers of 2. - F. Chapoton, Nov 04 2020
FORMULA
T(n,k) = t(n-k, k); t(0,0) = 1, t(n,m) = 0 if n < 0 or m < 0, else t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), where f(x) = 4*x + 2.
T(n, k) = (a*k + b)*T(n-1, k) + (a*(n-k) + b)*T(n-1, k-1), with T(n, 0) = 1, a = 4, and b = 2. - G. C. Greubel, Mar 20 2022
EXAMPLE
Triangle begins as:
1;
2, 2;
4, 24, 4;
8, 184, 184, 8;
16, 1216, 3680, 1216, 16;
32, 7584, 53824, 53824, 7584, 32;
64, 46208, 674752, 1507072, 674752, 46208, 64;
128, 278912, 7764096, 33244544, 33244544, 7764096, 278912, 128;
MATHEMATICA
T[n_, k_, a_, b_]:= T[n, k, a, b]= If[k<0 || k>n, 0, If[n==0, 1, (a*(n-k)+b)*T[n-1, k-1, a, b] + (a*k+b)*T[n-1, k, a, b]]];
Table[T[n, k, 4, 2], {n, 0, 12}, {k, 0, n}]//Flatten (* G. C. Greubel, Mar 20 2022 *)
PROG
(PARI) f(x) = 4*x + 2;
T(n, k) = t(n-k, k);
t(n, m) = if (!n && !m, 1, if (n < 0 || m < 0, 0, f(m)*t(n-1, m) + f(n)*t(n, m-1)));
tabl(nn) = for (n=0, nn, for (k=0, n, print1(T(n, k), ", "); ); print(); ); \\ Michel Marcus, May 06 2015
(Sage)
if (k<0 or k>n): return 0
elif (n==0): return 1
else: return (a*k+b)*T(n-1, k, a, b) + (a*(n-k)+b)*T(n-1, k-1, a, b)
flatten([[T(n, k, 4, 2) for k in (0..n)] for n in (0..12)]) # G. C. Greubel, Mar 20 2022
CROSSREFS
See similar sequences listed in A256890.
Triangle read by rows: T(n, k) = t(n-k, k), where t(0,0) = 1, t(n,m) = 0 if n < 0 or m < 0, else t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), and f(n) = 5*n + 2.
+10
10
1, 2, 2, 4, 28, 4, 8, 244, 244, 8, 16, 1844, 5856, 1844, 16, 32, 13260, 101620, 101620, 13260, 32, 64, 93684, 1511160, 3455080, 1511160, 93684, 64, 128, 657836, 20663388, 91981880, 91981880, 20663388, 657836, 128, 256, 4609588, 269011408, 2121603436, 4047202720, 2121603436, 269011408, 4609588, 256
FORMULA
T(n, k) = t(n-k, k), where t(0,0) = 1, t(n,m) = 0 if n < 0 or m < 0, else t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), and f(n) = 5*n + 2.
t(k, n) = t(n, k).
T(n, n-k) = T(n, k).
t(0, n) = T(n, 0) = A000079(n). (End)
EXAMPLE
Array t(n,k) begins as:
2, 28, 244, 1844, 13260, ...;
4, 244, 5856, 101620, 1511160, ...;
8, 1844, 101620, 3455080, 91981880, ...;
16, 13260, 1511160, 91981880, 4047202720, ...;
32, 93684, 20663388, 2121603436, 146321752612, ...;
64, 657836, 269011408, 44675623468, 4648698508440, ...;
Triangle T(n,k) begins as:
1;
2, 2;
4, 28, 4;
8, 244, 244, 8;
16, 1844, 5856, 1844, 16;
32, 13260, 101620, 101620, 13260, 32;
64, 93684, 1511160, 3455080, 1511160, 93684, 64;
128, 657836, 20663388, 91981880, 91981880, 20663388, 657836, 128;
MATHEMATICA
t[n_, k_, p_, q_]:= t[n, k, p, q] = If[n<0 || k<0, 0, If[n==0 && k==0, 1, (p*k+q)*t[n-1, k, p, q] + (p*n+q)*t[n, k-1, p, q]]];
T[n_, k_, p_, q_]= t[n-k, k, p, q];
Table[T[n, k, 5, 2], {n, 0, 12}, {k, 0, n}]//Flatten (* G. C. Greubel, Mar 01 2022 *)
PROG
(Sage)
@CachedFunction
def t(n, k, p, q):
if (n<0 or k<0): return 0
elif (n==0 and k==0): return 1
else: return (p*k+q)*t(n-1, k, p, q) + (p*n+q)*t(n, k-1, p, q)
def A257614(n, k): return t(n-k, k, 5, 2)
CROSSREFS
Similar sequences listed in A256890.
Triangle read by rows: T(n,k) = t(n-k, k); t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), where f(x) = 6*x + 2.
+10
10
1, 2, 2, 4, 32, 4, 8, 312, 312, 8, 16, 2656, 8736, 2656, 16, 32, 21664, 175424, 175424, 21664, 32, 64, 174336, 3019200, 7016960, 3019200, 174336, 64, 128, 1397120, 47847552, 218838400, 218838400, 47847552, 1397120, 128, 256, 11182592, 722956288, 5907889664, 11379596800, 5907889664, 722956288, 11182592, 256
FORMULA
T(n,k) = t(n-k, k); t(0,0) = 1, t(n,m) = 0 if n < 0 or m < 0, else t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), where f(x) = 6*x + 2.
T(n, k) = (a*k + b)*T(n-1, k) + (a*(n-k) + b)*T(n-1, k-1), with T(n, 0) = 1, a = 6, and b = 2.
T(n, n-k) = T(n, k).
T(n, 1) = (2^n/3)*(2^(2*n+1) - (3*n+2)). (End)
EXAMPLE
Triangle begins as:
1;
2, 2;
4, 32, 4;
8, 312, 312, 8;
16, 2656, 8736, 2656, 16;
32, 21664, 175424, 175424, 21664, 32;
64, 174336, 3019200, 7016960, 3019200, 174336, 64;
128, 1397120, 47847552, 218838400, 218838400, 47847552, 1397120, 128;
MATHEMATICA
T[n_, k_, a_, b_]:= T[n, k, a, b]= If[k<0 || k>n, 0, If[n==0, 1, (a*(n-k)+b)*T[n-1, k-1, a, b] + (a*k+b)*T[n-1, k, a, b]]];
Table[T[n, k, 6, 2], {n, 0, 12}, {k, 0, n}]//Flatten (* G. C. Greubel, Mar 21 2022 *)
PROG
(Sage)
if (k<0 or k>n): return 0
elif (n==0): return 1
else: return (a*k+b)*T(n-1, k, a, b) + (a*(n-k)+b)*T(n-1, k-1, a, b)
flatten([[T(n, k, 6, 2) for k in (0..n)] for n in (0..12)]) # G. C. Greubel, Mar 21 2022
CROSSREFS
Similar sequences listed in A256890.
Triangle read by rows: T(n,k) = t(n-k, k); t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), where f(x) = 7*x + 2.
+10
10
1, 2, 2, 4, 36, 4, 8, 388, 388, 8, 16, 3676, 12416, 3676, 16, 32, 33564, 283204, 283204, 33564, 32, 64, 303260, 5538184, 13027384, 5538184, 303260, 64, 128, 2732156, 99831564, 465775352, 465775352, 99831564, 2732156, 128
FORMULA
T(n,k) = t(n-k, k); t(0,0) = 1, t(n,m) = 0 if n < 0 or m < 0, else t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), where f(x) = 7*x + 2.
T(n, k) = (a*k + b)*T(n-1, k) + (a*(n-k) + b)*T(n-1, k-1), with T(n, 0) = 1, a = 7, and b = 2.
T(n, n-k) = T(n, k).
T(n, 1) = (4*9^n - 2^n*(7*n + 4))/7.
T(n, 2) = (2^(n-1)*(49*n^2 +7*n -12) + 11*2^(4*n+1) - 4*(7*n+4)*9^n)/49. (End)
EXAMPLE
1;
2, 2;
4, 36, 4;
8, 388, 388, 8;
16, 3676, 12416, 3676, 16;
32, 33564, 283204, 283204, 33564, 32;
64, 303260, 5538184, 13027384, 5538184, 303260, 64;
128, 2732156, 99831564, 465775352, 465775352, 99831564, 2732156, 128;
MATHEMATICA
T[n_, k_, a_, b_]:= T[n, k, a, b]= If[k<0 || k>n, 0, If[n==0, 1, (a*(n-k)+b)*T[n-1, k-1, a, b] + (a*k+b)*T[n-1, k, a, b]]];
Table[T[n, k, 7, 2], {n, 0, 12}, {k, 0, n}]//Flatten (* G. C. Greubel, Mar 24 2022 *)
PROG
(Sage)
if (k<0 or k>n): return 0
elif (n==0): return 1
else: return (a*k+b)*T(n-1, k, a, b) + (a*(n-k)+b)*T(n-1, k-1, a, b)
flatten([[T(n, k, 7, 2) for k in (0..n)] for n in (0..12)]) # G. C. Greubel, Mar 24 2022
CROSSREFS
Similar sequences listed in A256890.
Triangle read by rows: T(n,k) = t(n-k, k); t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), where f(x) = 9*x + 2.
+10
10
1, 2, 2, 4, 44, 4, 8, 564, 564, 8, 16, 6436, 22560, 6436, 16, 32, 71404, 637844, 637844, 71404, 32, 64, 786948, 15470232, 36994952, 15470232, 786948, 64, 128, 8660012, 346391196, 1660722424, 1660722424, 346391196, 8660012, 128
FORMULA
T(n,k) = t(n-k, k); t(0,0) = 1, t(n,m) = 0 if n < 0 or m < 0, else t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), where f(x) = 9*x + 2.
T(n, k) = (a*k + b)*T(n-1, k) + (a*(n-k) + b)*T(n-1, k-1), with T(n, 0) = 1, a = 9, and b = 2.
T(n, n-k) = T(n, k).
T(n, 1) = (1/9)*(4*11^n - 2^n*(9*n + 4)).
T(n, 2) = (1/81)*(26*20^n - 4*(4+9*n)*11^n - 2^(n-1)*(20 + 9*n - 81*n^2)). (End)
EXAMPLE
Triangle begins as:
1;
2, 2;
4, 44, 4;
8, 564, 564, 8;
16, 6436, 22560, 6436, 16;
32, 71404, 637844, 637844, 71404, 32;
64, 786948, 15470232, 36994952, 15470232, 786948, 64;
128, 8660012, 346391196, 1660722424, 1660722424, 346391196, 8660012, 128;
MATHEMATICA
T[n_, k_, a_, b_]:= T[n, k, a, b]= If[k<0 || k>n, 0, If[n==0, 1, (a*(n-k)+b)*T[n-1, k-1, a, b] + (a*k+b)*T[n-1, k, a, b]]];
Table[T[n, k, 9, 2], {n, 0, 12}, {k, 0, n}]//Flatten (* G. C. Greubel, Mar 24 2022 *)
PROG
(PARI) f(x) = 9*x + 2;
t(n, m) = if ((n<0) || (m<0), 0, if ((n==0) && (m==0), 1, f(m)*t(n-1, m) + f(n)*t(n, m-1)));
tabl(nn) = {for (n=0, nn, for (k=0, n, print1(t(n-k, k), ", "); ); print(); ); } \\ Michel Marcus, May 23 2015
(Sage)
if (k<0 or k>n): return 0
elif (n==0): return 1
else: return (a*k+b)*T(n-1, k, a, b) + (a*(n-k)+b)*T(n-1, k-1, a, b)
flatten([[T(n, k, 9, 2) for k in (0..n)] for n in (0..12)]) # G. C. Greubel, Mar 24 2022
CROSSREFS
Similar sequences listed in A256890.
Search completed in 0.016 seconds
|