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), (1, 0, 1), (1, 1, 1)}.

A150969

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), (1, 0, 1), (1, 1, 1)}.

Terms

    a(0) =1a(1) =2a(2) =9a(3) =36a(4) =156a(5) =708a(6) =3242a(7) =15036a(8) =70667a(9) =334535a(10) =1591110a(11) =7611704a(12) =36559791a(13) =176122332a(14) =850932300a(15) =4121606328a(16) =20003197132a(17) =97256045912a(18) =473643889965

External references