a(n) = 1 + Sum_{i=1..n} Sum_{j=1..n} i^j.

A124405

a(n) = 1 + Sum_{i=1..n} Sum_{j=1..n} i^j.

Terms

    a(0) =2a(1) =9a(2) =57a(3) =495a(4) =5700a(5) =82201a(6) =1419761a(7) =28501117a(8) =651233662a(9) =16676686697a(10) =472883843993

External references