OFFSET
1,5
LINKS
G. C. Greubel, Rows n = 1..50 of the triangle, flattened
G. Strasser, Generalisation of the Euler adic, Math. Proc. Camb. Phil. Soc. 150 (2010) 241-256, Triangle A_6(n,k).
FORMULA
T(n,k,m) = (m*n - m*k + 1)*T(n-1, k-1, m) + (m*k - (m-1))*T(n-1, k, m), with T(n, 1, m) = T(n, n, m) = 1, and m = 6.
Sum_{k=1..n} T(n, k, 6) = A047657(n-1).
EXAMPLE
Triangle begins as:
1;
1, 1;
1, 14, 1;
1, 111, 111, 1;
1, 796, 2886, 796, 1;
1, 5597, 52642, 52642, 5597, 1;
1, 39210, 824271, 2000396, 824271, 39210, 1;
1, 274507, 11931033, 58614299, 58614299, 11931033, 274507, 1;
MATHEMATICA
T[n_, k_, m_]:= T[n, k, m]= If[k==1 || k==n, 1, (m*n-m*k+1)*T[n-1, k-1, m] + (m*k -m+1)*T[n-1, k, m]];
A142461[n_, k_]:= T[n, k, 6];
Table[A142461[n, k], {n, 12}, {k, n}]//Flatten (* modified by G. C. Greubel, Mar 17 2022 *)
PROG
(Sage)
@CachedFunction
def T(n, k, m):
if (k==1 or k==n): return 1
else: return (m*(n-k)+1)*T(n-1, k-1, m) + (m*k-m+1)*T(n-1, k, m)
def A142461(n, k): return T(n, k, 6)
flatten([[ A142461(n, k) for k in (1..n)] for n in (1..15)]) # G. C. Greubel, Mar 17 2022
CROSSREFS
KEYWORD
AUTHOR
Roger L. Bagula, Sep 19 2008
EXTENSIONS
Edited by N. J. A. Sloane, May 08 2013
STATUS
approved