a(n) = A011916(n) + A011922(n) - 1.

A011918

a(n) = A011916(n) + A011922(n) - 1.

Terms

    a(0) =5a(1) =76a(2) =1065a(3) =14840a(4) =206701a(5) =2878980a(6) =40099025a(7) =558507376a(8) =7779004245a(9) =108347552060

External references