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Search: a355609 -id:a355609
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Square array T(n,k), n>=0, k>=0, read by antidiagonals, where column k is the expansion of e.g.f. (1 + x)^(x^k).
+10
6
1, 1, 1, 1, 0, 0, 1, 0, 2, 0, 1, 0, 0, -3, 0, 1, 0, 0, 6, 20, 0, 1, 0, 0, 0, -12, -90, 0, 1, 0, 0, 0, 24, 40, 594, 0, 1, 0, 0, 0, 0, -60, 180, -4200, 0, 1, 0, 0, 0, 0, 120, 240, -1512, 34544, 0, 1, 0, 0, 0, 0, 0, -360, -1260, 11760, -316008, 0, 1, 0, 0, 0, 0, 0, 720, 1680, 28224, -38880, 3207240, 0
OFFSET
0,9
LINKS
FORMULA
T(0,k) = 1 and T(n,k) = -(n-1)! * Sum_{j=k+1..n} (-1)^(j-k) * j/(j-k) * T(n-j,k)/(n-j)! for n > 0.
T(n,k) = n! * Sum_{j=0..floor(n/(k+1))} Stirling1(n-k*j,j)/(n-k*j)!.
EXAMPLE
Square array begins:
1, 1, 1, 1, 1, 1, 1, ...
1, 0, 0, 0, 0, 0, 0, ...
0, 2, 0, 0, 0, 0, 0, ...
0, -3, 6, 0, 0, 0, 0, ...
0, 20, -12, 24, 0, 0, 0, ...
0, -90, 40, -60, 120, 0, 0, ...
0, 594, 180, 240, -360, 720, 0, ...
PROG
(PARI) T(n, k) = n!*sum(j=0, n\(k+1), stirling(n-k*j, j, 1)/(n-k*j)!);
CROSSREFS
Columns k=1..4 give A007113, A007121, (-1)^n * A353229(n), A354625.
KEYWORD
sign,tabl,look
AUTHOR
Seiichi Manyama, Jul 09 2022
STATUS
approved
Square array T(n,k), n>=0, k>=0, read by antidiagonals, where column k is the expansion of e.g.f. (1 - x)^(-x^k/k!).
+10
6
1, 1, 1, 1, 0, 2, 1, 0, 2, 6, 1, 0, 0, 3, 24, 1, 0, 0, 3, 20, 120, 1, 0, 0, 0, 6, 90, 720, 1, 0, 0, 0, 4, 20, 594, 5040, 1, 0, 0, 0, 0, 10, 180, 4200, 40320, 1, 0, 0, 0, 0, 5, 40, 1134, 34544, 362880, 1, 0, 0, 0, 0, 0, 15, 210, 7980, 316008, 3628800, 1, 0, 0, 0, 0, 0, 6, 70, 1904, 71280, 3207240, 39916800
OFFSET
0,6
LINKS
FORMULA
T(0,k) = 1 and T(n,k) = (n-1)!/k! * Sum_{j=k+1..n} j/(j-k) * T(n-j,k)/(n-j)! for n > 0.
T(n,k) = n! * Sum_{j=0..floor(n/(k+1))} |Stirling1(n-k*j,j)|/(k!^j * (n-k*j)!).
EXAMPLE
Square array begins:
1, 1, 1, 1, 1, 1, 1, ...
1, 0, 0, 0, 0, 0, 0, ...
2, 2, 0, 0, 0, 0, 0, ...
6, 3, 3, 0, 0, 0, 0, ...
24, 20, 6, 4, 0, 0, 0, ...
120, 90, 20, 10, 5, 0, 0, ...
720, 594, 180, 40, 15, 6, 0, ...
PROG
(PARI) T(n, k) = n!*sum(j=0, n\(k+1), abs(stirling(n-k*j, j, 1))/(k!^j*(n-k*j)!));
CROSSREFS
Columns k=0..4 give A000142, A066166, A351492, A351493, A355507.
KEYWORD
nonn,tabl
AUTHOR
Seiichi Manyama, Jul 09 2022
STATUS
approved
Expansion of e.g.f. (1 - x)^(-x^4).
+10
2
1, 0, 0, 0, 0, 120, 360, 1680, 10080, 72576, 2419200, 25660800, 279417600, 3286483200, 41894012160, 794511244800, 13755488947200, 238514695372800, 4269265386946560, 79696849513881600, 1658065431859200000
OFFSET
0,6
FORMULA
a(0) = 1; a(n) = (n-1)! * Sum_{k=5..n} k/(k-4) * a(n-k)/(n-k)!.
a(n) = n! * Sum_{k=0..floor(n/5)} |Stirling1(n-4*k,k)|/(n-4*k)!.
a(n) ~ n! * (1 - 4/n - 16*log(n)/n^2). - Vaclav Kotesovec, Jul 21 2022
PROG
(PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace((1-x)^(-x^4)))
(PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(exp(-x^4*log(1-x))))
(PARI) a_vector(n) = my(v=vector(n+1)); v[1]=1; for(i=1, n, v[i+1]=(i-1)!*sum(j=5, i, j/(j-4)*v[i-j+1]/(i-j)!)); v;
(PARI) a(n) = n!*sum(k=0, n\5, abs(stirling(n-4*k, k, 1))/(n-4*k)!);
CROSSREFS
Column k=4 of A355609.
Cf. A354625.
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Jul 09 2022
STATUS
approved
Square array T(n,k), n>=0, k>=0, read by antidiagonals, where column k is the expansion of e.g.f. 1/(1 + x^k * log(1 - x)).
+10
1
1, 1, 1, 1, 0, 3, 1, 0, 2, 14, 1, 0, 0, 3, 88, 1, 0, 0, 6, 32, 694, 1, 0, 0, 0, 12, 150, 6578, 1, 0, 0, 0, 24, 40, 1524, 72792, 1, 0, 0, 0, 0, 60, 900, 12600, 920904, 1, 0, 0, 0, 0, 120, 240, 6048, 147328, 13109088, 1, 0, 0, 0, 0, 0, 360, 1260, 43680, 1705536, 207360912
OFFSET
0,6
FORMULA
T(0,k) = 1 and T(n,k) = n! * Sum_{j=k+1..n} 1/(j-k) * T(n-j,k)/(n-j)! for n > 0.
T(n,k) = n! * Sum_{j=0..floor(n/(k+1))} j! * |Stirling1(n-k*j,j)|/(n-k*j)!.
EXAMPLE
Square array begins:
1, 1, 1, 1, 1, 1, 1, ...
1, 0, 0, 0, 0, 0, 0, ...
3, 2, 0, 0, 0, 0, 0, ...
14, 3, 6, 0, 0, 0, 0, ...
88, 32, 12, 24, 0, 0, 0, ...
694, 150, 40, 60, 120, 0, 0, ...
6578, 1524, 900, 240, 360, 720, 0, ...
PROG
(PARI) T(n, k) = n!*sum(j=0, n\(k+1), j!*abs(stirling(n-k*j, j, 1))/(n-k*j)!);
CROSSREFS
Columns k=0..3 give A007840, A052830, A351503, A351504.
KEYWORD
nonn,tabl
AUTHOR
Seiichi Manyama, Jul 13 2022
STATUS
approved

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