a(n) = 2^(2*n+1)*Sum_{k=1..2*n} binomial(2*n+1,k)*Bernoulli(k)/2^k.

A069993

a(n) = 2^(2*n+1)*Sum_{k=1..2*n} binomial(2*n+1,k)*Bernoulli(k)/2^k.

Terms

    a(0) =5a(1) =27a(2) =121a(3) =503a(4) =2037a(5) =8179a(6) =32753a(7) =131055a(8) =524269a(9) =2097131a(10) =8388585a(11) =33554407a(12) =134217701a(13) =536870883a(14) =2147483617a(15) =8589934559a(16) =34359738333a(17) =137438953435a(18) =549755813849

External references