a(n) = Sum_{k=0..n} (3*k+1) * binomial(5*n-2*k+1,n-k)/(5*n-2*k+1).
A390712
a(n) = Sum_{k=0..n} (3*k+1) * binomial(5*n-2*k+1,n-k)/(5*n-2*k+1).
Terms
- a(0) =1a(1) =2a(2) =10a(3) =69a(4) =556a(5) =4900a(6) =45761a(7) =445031a(8) =4459282a(9) =45720003a(10) =477353196a(11) =5057982974a(12) =54251905261a(13) =587910920213
External references
- oeis: A390712