a(n) = 2^(n - HammingWeight(n)) * binomial(2*n, n).

A371357

a(n) = 2^(n - HammingWeight(n)) * binomial(2*n, n).

Terms

    a(0) =1a(1) =2a(2) =12a(3) =40a(4) =560a(5) =2016a(6) =14784a(7) =54912a(8) =1647360a(9) =6223360a(10) =47297536a(11) =180590592a(12) =2769055744a(13) =10650214400a(14) =82158796800a(15) =317680680960

External references