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, 0, 1), (1, 0, -1), (1, 1, -1)}.
A148690
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, 0, 1), (1, 0, -1), (1, 1, -1)}.
Terms
- a(0) =1a(1) =1a(2) =3a(3) =7a(4) =23a(5) =66a(6) =225a(7) =760a(8) =2635a(9) =9326a(10) =34170a(11) =125303a(12) =465172a(13) =1760793a(14) =6717459a(15) =25686249a(16) =99508522a(17) =388671862a(18) =1520793455a(19) =5988924457a(20) =23774733713a(21) =94606934110a(22) =377603437450
External references
- oeis: A148690