a(n) = Sum_{k=0..n} binomial(n+3*k+3,n-k) * Catalan(k).
A358518
a(n) = Sum_{k=0..n} binomial(n+3*k+3,n-k) * Catalan(k).
Terms
- a(0) =1a(1) =5a(2) =20a(3) =85a(4) =405a(5) =2116a(6) =11766a(7) =68237a(8) =407789a(9) =2492553a(10) =15506942a(11) =97859544a(12) =624880895a(13) =4029896310a(14) =26209648212a(15) =171711104853
External references
- oeis: A358518