a(n) = (2^floor(n+n/2)/sqrt(Pi)^mod(n+1,2))*Gamma(n+1/2)/Gamma(n/2+1).

A264152

a(n) = (2^floor(n+n/2)/sqrt(Pi)^mod(n+1,2))*Gamma(n+1/2)/Gamma(n/2+1).

Terms

    a(0) =1a(1) =2a(2) =6a(3) =40a(4) =210a(5) =2016a(6) =13860a(7) =164736a(8) =1351350a(9) =18670080a(10) =174594420a(11) =2708858880a(12) =28109701620a(13) =479259648000

External references