a(n) = floor(Pi^n / e).

Terms

a(0) =0a(1) =1a(2) =3a(3) =11a(4) =35a(5) =112a(6) =353a(7) =1111a(8) =3490a(9) =10966a(10) =34451a(11) =108231a(12) =340019a(13) =1068203a(14) =3355859a(15) =10542742a(16) =33121003a(17) =104052699a(18) =326891197a(19) =1026958985a(20) =3226286805a(21) =10135678925a(22) =31842174452a(23) =100035141333a(24) =314269665113a(25) =987307271166