a(n) = Sum_{k = 0..n} ( binomial(n+k-1,k) + binomial(n+k-1,k)^2 ).
A357671
a(n) = Sum_{k = 0..n} ( binomial(n+k-1,k) + binomial(n+k-1,k)^2 ).
Terms
- a(0) =2a(1) =4a(2) =20a(3) =166a(4) =1812a(5) =22504a(6) =297362a(7) =4067298a(8) =56897300a(9) =809019580a(10) =11649254520a(11) =169444978124
External references
- oeis: A357671