a(n) = Sum_{k=0..n} binomial(5*n+k-1,n-k).
A390339
a(n) = Sum_{k=0..n} binomial(5*n+k-1,n-k).
Terms
- a(0) =1a(1) =5a(2) =47a(3) =486a(4) =5249a(5) =58134a(6) =654514a(7) =7455031a(8) =85652055a(9) =990691064a(10) =11520294266a(11) =134551636752
External references
- oeis: A390339