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), (0, 1), (1, 0)}.
A151464
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), (0, 1), (1, 0)}.
Terms
- a(0) =1a(1) =1a(2) =4a(3) =12a(4) =46a(5) =180a(6) =745a(7) =3185a(8) =14000a(9) =62832a(10) =287154a(11) =1331484a(12) =6251916a(13) =29671356a(14) =142132848a(15) =686420592a(16) =3338939032a(17) =16345771728a(18) =80480627656a(19) =398307700648
External references
- oeis: A151464