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, -1, 0), (-1, 1, 0), (1, 0, -1), (1, 0, 1)}.
A148733
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, -1, 0), (-1, 1, 0), (1, 0, -1), (1, 0, 1)}.
Terms
- a(0) =1a(1) =1a(2) =3a(3) =7a(4) =25a(5) =77a(6) =285a(7) =913a(8) =3701a(9) =13063a(10) =52643a(11) =188689a(12) =798789a(13) =3006633a(14) =12625037a(15) =47906009a(16) =207521071a(17) =812293015a(18) =3492286581a(19) =13719773237a(20) =60326990057a(21) =242352250509
External references
- oeis: A148733