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), (0, -1), (0, 1), (1, -1)}.
A151425
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), (0, -1), (0, 1), (1, -1)}.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =4a(4) =11a(5) =28a(6) =82a(7) =242a(8) =752a(9) =2379a(10) =7750a(11) =25692a(12) =86635a(13) =296558a(14) =1027851a(15) =3603503a(16) =12758718a(17) =45585878a(18) =164181411a(19) =595669369a(20) =2175535954a(21) =7994009929a(22) =29537993178a(23) =109704376600a(24) =409377743815
External references
- oeis: A151425