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

Terms

a(0) =1a(1) =3a(2) =9a(3) =31a(4) =97a(5) =306a(6) =961a(7) =3020a(8) =9488a(9) =29809a(10) =93648a(11) =294204a(12) =924269a(13) =2903677a(14) =9122171a(15) =28658145a(16) =90032220a(17) =282844563a(18) =888582403a(19) =2791563949a(20) =8769956796a(21) =27551631842a(22) =86556004191a(23) =271923706893a(24) =854273519913