a(0) = 1; a(n) = Sum_{k=1..n} prime(k+1)*a(n-k).

Terms

a(0) =1a(1) =3a(2) =14a(3) =64a(4) =294a(5) =1346a(6) =6166a(7) =28242a(8) =129362a(9) =592538a(10) =2714096a(11) =12431808a(12) =56943398a(13) =260826950a(14) =1194707382a(15) =5472309246a(16) =25065693008a(17) =114812401444a(18) =525893599720