a(n) = Sum_{k=0..n} (n+k+2)!/((n-k)!*k!*2^k).

A144513

a(n) = Sum_{k=0..n} (n+k+2)!/((n-k)!*k!*2^k).

Terms

    a(0) =2a(1) =18a(2) =162a(3) =1670a(4) =19980a(5) =274932a(6) =4296278a(7) =75324762a(8) =1466031690a(9) =31386435410a(10) =733391707752

External references