E.g.f.: 2 - exp(2) + Sum_{n>=1} 2^n * exp(x^n) / n!.

Terms

a(0) =1a(1) =2a(2) =6a(3) =10a(4) =42a(5) =34a(6) =786a(7) =130a(8) =17058a(9) =81154a(10) =545346a(11) =2050a(12) =102457218a(13) =8194a(14) =1141636866a(15) =72648608770a(16) =648648065538a(17) =131074a(19) =524290a(23) =8388610