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, 0), (0, -1, 0), (0, 1, -1), (1, 0, 1)}.
A148776
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, 0), (0, -1, 0), (0, 1, -1), (1, 0, 1)}.
Terms
- a(0) =1a(1) =1a(2) =3a(3) =8a(4) =23a(5) =70a(6) =231a(7) =747a(8) =2519a(9) =8596a(10) =30022a(11) =104652a(12) =372171a(13) =1327738a(14) =4795592a(15) =17329563a(16) =63304887a(17) =231602170a(18) =853989048a(19) =3150826452a(20) =11704071278a(21) =43519371188a(22) =162687329027a(23) =608474865891
External references
- oeis: A148776