a(n) = Sum_{k=0..n-3} T(n,k) * T(n,k+3), with T given by A026637.
A026969
a(n) = Sum_{k=0..n-3} T(n,k) * T(n,k+3), with T given by A026637.
Terms
- a(0) =1a(1) =10a(2) =75a(3) =372a(4) =1796a(5) =7796a(6) =33352a(7) =138790a(8) =571995a(9) =2334558a(10) =9473195a(11) =38258984a(12) =153981400a(13) =618042736a(14) =2475405456a(15) =9897862062a(16) =39523226642a(17) =157650156506a(18) =628287555844
External references
- oeis: A026969