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, 1), (0, 1, -1), (0, 1, 1), (1, 0, -1)}.
A148726
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, 1), (0, 1, -1), (0, 1, 1), (1, 0, -1)}.
Terms
- a(0) =1a(1) =1a(2) =3a(3) =7a(4) =25a(5) =72a(6) =278a(7) =916a(8) =3672a(9) =13025a(10) =53751a(11) =200217a(12) =843672a(13) =3257716a(14) =13933910a(15) =55297282a(16) =239315186a(17) =970147542a(18) =4239127095a(19) =17480675840a(20) =76987864204a(21) =321968327531
External references
- oeis: A148726