a(n) = Sum_{k=0..n-3} T(n,k) * T(n,k+3), with T given by A026769.
A027242
a(n) = Sum_{k=0..n-3} T(n,k) * T(n,k+3), with T given by A026769.
Terms
- a(0) =1a(1) =10a(2) =68a(3) =402a(4) =2258a(5) =12072a(6) =64963a(7) =338824a(8) =1817063a(9) =9467940a(10) =51258781a(11) =269085042a(12) =1475551064a(13) =7822940886a(14) =43422818989a(15) =232480179882
External references
- oeis: A027242