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, 0, 1), (0, 1, 1), (1, -1, 1), (1, 1, -1)}.
A148981
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, 0, 1), (0, 1, 1), (1, -1, 1), (1, 1, -1)}.
Terms
- a(0) =1a(1) =1a(2) =3a(3) =9a(4) =32a(5) =112a(6) =419a(7) =1556a(8) =5966a(9) =22800a(10) =88624a(11) =343953a(12) =1348203a(13) =5280871a(14) =20811229a(15) =81995438a(16) =324318955a(17) =1282789042a(18) =5086938010a(19) =20174850237a(20) =80153717254a(21) =318501840735
External references
- oeis: A148981