OFFSET
1,6
LINKS
M. Josuat-Vergès, J.-C. Novelli and J.-Y. Thibon, The algebraic combinatorics of snakes, arXiv preprint arXiv:1110.5272 [math.CO], 2011.
EXAMPLE
Triangle begins:
1 1
0 1 1 2
4 4 3 3 2 0
0 4 8 11 11 14 16 16
80 80 76 68 57 57 46 32 16 0
0 80 160 236 304 361 361 418 464 496 512 512
PROG
(PARI) T(n, k) = {if ((k==0), return(0)); if (n==1, if (abs(k)==1, return(1))); if (n%2, if (k<0, sum(j=k+1, n-1, T(n-1, j)), sum(j=k, n-1, T(n-1, j))), if (k<0, sum(j=-n+1, k, T(n-1, j)), sum(j=-n+1, k-1, T(n-1, j)))); }
tabf(nn) = {for (n=1, nn, for (k=-n, n, if (k, print1(T(n, k), ", ")); ); print; ); } \\ Michel Marcus, Jun 03 2020
CROSSREFS
KEYWORD
nonn,tabf
AUTHOR
N. J. A. Sloane, Dec 22 2011
EXTENSIONS
More terms from Michel Marcus, Jun 03 2020
STATUS
approved