a(n) = ((2^prime(n+2)-2)/prime(n+2))/3, where n >= 1.

A145756

a(n) = ((2^prime(n+2)-2)/prime(n+2))/3, where n >= 1.

Terms

    a(0) =2a(1) =6a(2) =62a(3) =210a(4) =2570a(5) =9198a(6) =121574a(7) =6170930a(8) =23091222a(9) =1238188770a(10) =17878237850a(11) =68186767614a(12) =998138215286

External references