a(n) = 2^n*Bell(n). E.g.f.: exp(exp(2*x)-1).

A055882

a(n) = 2^n*Bell(n). E.g.f.: exp(exp(2*x)-1).

Terms

    a(0) =1a(1) =2a(2) =8a(3) =40a(4) =240a(5) =1664a(6) =12992a(7) =112256a(8) =1059840a(9) =10827264a(10) =118758400a(11) =1389711360a(12) =17258893312a(13) =226463227904

External references