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A148870 Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 1), (-1, 0, 0), (0, 1, -1), (0, 1, 1), (1, -1, 0)} 0
1, 1, 3, 8, 29, 94, 345, 1279, 5059, 19688, 79177, 322253, 1334084, 5547509, 23402949, 99466276, 425275371, 1829109184, 7928585175, 34530360916, 150984395695, 663332004284, 2927093664726, 12956211856289, 57535449125651, 256405536186925, 1145894330679809, 5133168091473457, 23054569551952657 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Table of n, a(n) for n=0..28.

A. Bostan and M. Kauers, 2008. Automatic Classification of Restricted Lattice Walks, ArXiv 0811.2899.

MATHEMATICA

aux[i_Integer, j_Integer, k_Integer, n_Integer] := Which[Min[i, j, k, n] < 0 || Max[i, j, k] > n, 0, n == 0, KroneckerDelta[i, j, k, n], True, aux[i, j, k, n] = aux[-1 + i, 1 + j, k, -1 + n] + aux[i, -1 + j, -1 + k, -1 + n] + aux[i, -1 + j, 1 + k, -1 + n] + aux[1 + i, j, k, -1 + n] + aux[1 + i, 1 + j, -1 + k, -1 + n]]; Table[Sum[aux[i, j, k, n], {i, 0, n}, {j, 0, n}, {k, 0, n}], {n, 0, 10}]

CROSSREFS

Sequence in context: A063546 A148868 A148869 * A148871 A148872 A148873

Adjacent sequences:  A148867 A148868 A148869 * A148871 A148872 A148873

KEYWORD

nonn,walk

AUTHOR

Manuel Kauers, Nov 18 2008

STATUS

approved

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Last modified September 23 18:51 EDT 2020. Contains 337315 sequences. (Running on oeis4.)