A026151 a(n) = T(n,n), where T is the array in A026148.

1, 1, 2, 4, 12, 32, 89, 246, 685, 1912, 5355, 15038, 42339, 119484, 337935, 957738, 2719539, 7736208, 22044444, 62916696, 179841270, 514793944, 1475586687, 4234989242, 12169352003, 35009302296, 100826681530, 290683486132, 838873595124

Offset: 0

Author

Clark Kimberling

Keywords

• nonn

Crossrefs

Cf. A026148

First differences of A026325 for n > 1.

Extensions

a(0)-a(1) inserted and a(20) corrected by Sean A. Irvine, Sep 18 2019