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, 0), (-1, 0, -1), (0, 1, 1), (1, -1, 1), (1, 1, -1)}.
A149021
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, 0), (-1, 0, -1), (0, 1, 1), (1, -1, 1), (1, 1, -1)}.
Terms
- a(0) =1a(1) =1a(2) =3a(3) =9a(4) =37a(5) =131a(6) =545a(7) =2177a(8) =9355a(9) =39977a(10) =174857a(11) =769069a(12) =3431629a(13) =15420969a(14) =69990327a(15) =318835947a(16) =1462455953a(17) =6736988177a(18) =31195991605a(19) =145064556281a(20) =676590943343
External references
- oeis: A149021