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), (1, 0, 1), (1, 1, -1)}.
A148801
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), (1, 0, 1), (1, 1, -1)}.
Terms
- a(0) =1a(1) =1a(2) =3a(3) =8a(4) =26a(5) =78a(6) =271a(7) =896a(8) =3228a(9) =11119a(10) =41002a(11) =145548a(12) =545187a(13) =1974923a(14) =7480699a(15) =27503349a(16) =105050951a(17) =390597492a(18) =1501505042a(19) =5632087999a(20) =21759951598a(21) =82196014521a(22) =318859845293
External references
- oeis: A148801