Integer part of Sum_{i=1..n} binomial(n,i) * (n/i)^i.

Terms

a(0) =1a(1) =5a(2) =16a(3) =50a(4) =147a(5) =422a(6) =1210a(7) =3459a(8) =9878a(9) =28189a(10) =80425a(11) =229411a(12) =654311a(13) =1866003a(14) =5321194a(15) =15173321a(16) =43264523a(17) =123357771a(18) =351712022a(19) =1002758190a(20) =2858875748a(21) =8150529454a(22) =23236408366a(23) =66243882238a(24) =188849982251a(25) =538372895393