A026949 a(n) = Sum_{k=0..n-3} T(n,k) * T(n,k+3), with T given by A026374.

1, 12, 83, 630, 3171, 21672, 97482, 639180, 2730615, 17543196, 72932904, 463291920, 1895949055, 11961944400, 48478715240, 304543085040, 1226501910315, 7682898791700, 30811853728475, 192632866196694, 770315837004637, 4809438625979592, 19193549752057758, 119719958370912900

Offset: 3

Author

Clark Kimberling

Keywords

• nonn

Crossrefs

Cf. A026374.

Extensions

More terms from Sean A. Irvine, Oct 17 2019