a(n) = Sum_{k=0..n-1} binomial(4*k-1,k) * binomial(4*n-4*k,n-k-1).
A386565
a(n) = Sum_{k=0..n-1} binomial(4*k-1,k) * binomial(4*n-4*k,n-k-1).
Terms
- a(0) =0a(1) =1a(2) =11a(3) =111a(4) =1091a(5) =10596a(6) =102237a(7) =982458a(8) =9415539a(9) =90063180a(10) =860278156a(11) =8208539351a(12) =78258171957a(13) =745595635084
External references
- oeis: A386565