a(n) = denominator of sum_(k=1..n) 1/(2*k-1)^n.A234145a(n) = denominator of sum_(k=1..n) 1/(2*k-1)^n.Terms a(0) =1a(1) =1a(2) =9a(3) =3375a(4) =121550625External referencesoeis: A234145