a(n) = Sum_{d|n} (2*d+1)^n.A367509a(n) = Sum_{d|n} (2*d+1)^n.Terms a(0) =3a(1) =34a(2) =370a(3) =7267a(4) =161294a(5) =4960812a(6) =170861562a(7) =7019201348a(8) =322728071069External referencesoeis: A367509