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A202690
The triangle in A185356 with the central column of zeros omitted.
6
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, 3904, 3904, 3824, 3664, 3428, 3124, 2763, 2763, 2402, 1984, 1520, 1024, 512, 0
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