a(n) = (Product_{i=1..6} n^i+i) / 6!.A131676a(n) = (Product_{i=1..6} n^i+i) / 6!.Terms a(0) =1a(1) =7a(2) =14245a(3) =28405300a(4) =9191136045a(5) =886286703456External referencesoeis: A131676