a(1)=1 then a(n)= (1/2) *(5*a(n-1)+1) if a(n-1) is odd, a(n)=3/2*a(n-1) otherwise.

Terms

a(0) =1a(1) =3a(2) =8a(3) =12a(4) =18a(5) =27a(6) =68a(7) =102a(8) =153a(9) =383a(10) =958a(11) =1437a(12) =3593a(13) =8983a(14) =22458a(15) =33687a(16) =84218a(17) =126327a(18) =315818a(19) =473727a(20) =1184318a(21) =1776477a(22) =4441193a(23) =11102983a(24) =27757458a(25) =41636187a(26) =104090468a(27) =156135702a(28) =234203553a(29) =585508883