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, 1), (0, -1), (1, 0), (1, 1)}.

A151438

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, 1), (0, -1), (1, 0), (1, 1)}.

Terms

    a(0) =1a(1) =0a(2) =3a(3) =3a(4) =25a(5) =58a(6) =302a(7) =1000a(8) =4572a(9) =17759a(10) =78402a(11) =327746a(12) =1445868a(13) =6280646a(14) =27957450a(15) =124210073a(16) =558853524a(17) =2520567027a(18) =11454557485a(19) =52237087015a(20) =239457095960

External references