OFFSET
1,2
LINKS
Andrew Howroyd, Table of n, a(n) for n = 1..1276 (rows 1..25)
D. H. Lehmer, Generalized Eulerian numbers, J. Combin. Theory Ser.A 32 (1982), no. 2, 195-215. MR0654621 (83k:10026).
FORMULA
A047683(n) = Sum_{k>=1} T(2*n, k). - Andrew Howroyd, May 18 2020
EXAMPLE
Triangle begins:
1, 2, 3, 4;
1, 4, 10, 20, 10, 4, 1;
1, 7, 27, 77, 57, 0, -57, -77, -27, -7, -1;
...
PROG
(PARI)
T(n, r=4)={my(R=vector(n)); R[1]=[1..r]; for(n=2, n, my(u=R[n-1]); R[n]=vector(r*n-1, k, sum(j=0, r, (k - j*n)*if(k>j && k-j<=#u, u[k-j], 0)))); R}
{ my(A=T(5)); for(n=1, #A, print(A[n])) } \\ Andrew Howroyd, May 18 2020
CROSSREFS
KEYWORD
sign,tabf
AUTHOR
N. J. A. Sloane, Apr 05 2012
EXTENSIONS
More terms from Franck Maminirina Ramaharo, Nov 30 2018
a(20) corrected by Andrew Howroyd, May 18 2020
STATUS
approved