Number of walks within N^2 (the first quadrant of Z^2) starting at (0,0), ending on the vertical axis and consisting of n steps taken from {(-1, -1), (-1, 0), (-1, 1), (0, 1), (1, -1), (1, 0)}.
A151468
Number of walks within N^2 (the first quadrant of Z^2) starting at (0,0), ending on the vertical axis and consisting of n steps taken from {(-1, -1), (-1, 0), (-1, 1), (0, 1), (1, -1), (1, 0)}.
Terms
- a(0) =1a(1) =1a(2) =3a(3) =11a(4) =38a(5) =157a(6) =658a(7) =2892a(8) =13148a(9) =61075a(10) =290365a(11) =1402947a(12) =6881643a(13) =34184251a(14) =171674635a(15) =870572065a(16) =4452380910a(17) =22945034368a(18) =119053691259a(19) =621535445725
External references
- oeis: A151468