a(n) = floor(5^n/2^n).

Terms

a(0) =1a(1) =2a(2) =6a(3) =15a(4) =39a(5) =97a(6) =244a(7) =610a(8) =1525a(9) =3814a(10) =9536a(11) =23841a(12) =59604a(13) =149011a(14) =372529a(15) =931322a(16) =2328306a(17) =5820766a(18) =14551915a(19) =36379788a(20) =90949470a(21) =227373675a(22) =568434188a(23) =1421085471a(24) =3552713678a(25) =8881784197a(26) =22204460492a(27) =55511151231a(28) =138777878078a(29) =346944695195