Number of walks within N^2 (the first quadrant of Z^2) starting at (0,0) and consisting of n steps taken from {(-1, -1), (-1, 1), (-1, 0), (0, 1), (1, 0)}.
A151285
Number of walks within N^2 (the first quadrant of Z^2) starting at (0,0) and consisting of n steps taken from {(-1, -1), (-1, 1), (-1, 0), (0, 1), (1, 0)}.
Terms
- a(0) =1a(1) =2a(2) =6a(3) =20a(4) =70a(5) =257a(6) =967a(7) =3722a(8) =14548a(9) =57619a(10) =230612a(11) =931083a(12) =3787276a(13) =15502881a(14) =63810147a(15) =263909613a(16) =1096140669a(17) =4570019368a(18) =19117859437a(19) =80220313298a(20) =337542496835
External references
- oeis: A151285