A227658 Number of lattice paths from {4}^n to {0}^n using steps that decrement one component by 1 such that for each point (p_1,p_2,...,p_n) we have abs(p_{i}-p_{i+1}) <= 1.

1, 1, 16, 2328, 1281696, 1897242448, 6173789662504, 38746316631586896, 427196257460311066608, 7716228754248308194763776, 216245142312150285990621189096, 9001993707519997876764394044746416, 537141544856485105833302134461795535280

Offset

0,3

Links

Table of n, a(n) for n=0..12.

Example

a(2) = 2^4 = 16:
.     (3,4)       (2,3)       (1,2)       (0,1)
.    /     \     /     \     /     \     /     \
(4,4)       (3,3)       (2,2)       (1,1)       (0,0)
.    \     /     \     /     \     /     \     /
.     (4,3)       (3,2)       (2,1)       (1,0)

Crossrefs

Row n=4 of A227655.

Sequence in context: A165126 A241368 A069443 * A298197 A016876 A221253

Adjacent sequences: A227655 A227656 A227657 * A227659 A227660 A227661

Keyword

nonn

Author

Alois P. Heinz, Jul 19 2013

Status

approved