a(n) = (3^(2^n) + 1)/2 = A059919(n)/2, n >= 0.A059917a(n) = (3^(2^n) + 1)/2 = A059919(n)/2, n >= 0.Terms a(0) =2a(1) =5a(2) =41a(3) =3281a(4) =21523361External referencesoeis: A059917