Powers of fifth root of 20 rounded up.

Terms

a(0) =1a(1) =2a(2) =4a(3) =7a(4) =11a(5) =20a(6) =37a(7) =67a(8) =121a(9) =220a(10) =400a(11) =729a(12) =1326a(13) =2414a(14) =4395a(15) =8000a(16) =14565a(17) =26516a(18) =48274a(19) =87885a(20) =160000a(21) =291291a(22) =530313a(23) =965469a(24) =1757697a(25) =3200000a(26) =5825806a(27) =10606253a(28) =19309365a(29) =35153938