Third column of triangle A067410 and second column of A067417.

A067411

Third column of triangle A067410 and second column of A067417.

Terms

    a(0) =1a(1) =4a(2) =24a(3) =144a(4) =864a(5) =5184a(6) =31104a(7) =186624a(8) =1119744a(9) =6718464a(10) =40310784a(11) =241864704a(12) =1451188224a(13) =8707129344a(14) =52242776064a(15) =313456656384

External references