A202815 The right-hand half-triangle of A185356 (or A202690).

1, 1, 2, 3, 2, 0, 11, 14, 16, 16, 57, 46, 32, 16, 0, 361, 418, 464, 496, 512, 512, 2763, 2402, 1984, 1520, 1024, 512, 0, 24611, 27374, 29776, 31760, 33280, 34304, 34816, 34816, 250737, 226126, 198752, 168976, 137216, 103936, 69632, 34816, 0

Offset

1,3

Links

Table of n, a(n) for n=1..45.

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   2
    3   2   0
   11  14  16  16
   57  46  32  16   0
  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)))); }
tabl(nn) = {for (n=1, nn, for (k=1, n, if (k, print1(T(n, k), ", ")); ); print; ); } \\ Michel Marcus, Jun 03 2020

Crossrefs

Cf. A185356, A202690, A202816.

Sequence in context: A152954 A079175 A332742 * A049336 A017888 A017878

Adjacent sequences: A202812 A202813 A202814 * A202816 A202817 A202818

Keyword

nonn,tabl

Author

N. J. A. Sloane, Dec 25 2011

Extensions

More terms from Michel Marcus, Jun 03 2020

Status

approved