a(n) = Sum_{k=0..n} (k+1) * 3^k * binomial(2*n+1,n-k).
A384365
a(n) = Sum_{k=0..n} (k+1) * 3^k * binomial(2*n+1,n-k).
Terms
- a(0) =1a(1) =9a(2) =67a(3) =458a(4) =2979a(5) =18750a(6) =115278a(7) =696372a(8) =4149283a(9) =24452534a(10) =142808922a(11) =827780684a(12) =4767638158a(13) =27309438252a(14) =155689424316a(15) =883891633896
External references
- oeis: A384365