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, 1, 1), (0, 0, -1), (0, 1, 1), (1, 0, -1)}.
A148727
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, 1, 1), (0, 0, -1), (0, 1, 1), (1, 0, -1)}.
Terms
- a(0) =1a(1) =1a(2) =3a(3) =7a(4) =25a(5) =72a(6) =278a(7) =918a(8) =3678a(9) =13008a(10) =53788a(11) =200502a(12) =844075a(13) =3258363a(14) =13943192a(15) =55340162a(16) =239449624a(17) =970569758a(18) =4241711654a(19) =17492540256a(20) =77030015096a(21) =322137728727
External references
- oeis: A148727