Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (-1, 1, 0), (0, 0, 1), (1, 0, -1)}.
A148072
Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (-1, 1, 0), (0, 0, 1), (1, 0, -1)}.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =4a(4) =9a(5) =21a(6) =56a(7) =148a(8) =421a(9) =1207a(10) =3535a(11) =10407a(12) =31879a(13) =97111a(14) =304344a(15) =958636a(16) =3045621a(17) =9696563a(18) =31478459a(19) =101764723a(20) =334038583a(21) =1100234409a(22) =3639933291a(23) =12057585459a(24) =40418753669a(25) =135042191401a(26) =455549125751
External references
- oeis: A148072