a(n) = 102*2^n - 108 (n>=1).

Terms

a(0) =96a(1) =300a(2) =708a(3) =1524a(4) =3156a(5) =6420a(6) =12948a(7) =26004a(8) =52116a(9) =104340a(10) =208788a(11) =417684a(12) =835476a(13) =1671060a(14) =3342228a(15) =6684564a(16) =13369236a(17) =26738580a(18) =53477268a(19) =106954644a(20) =213909396a(21) =427818900a(22) =855637908a(23) =1711275924a(24) =3422551956a(25) =6845104020a(26) =13690208148a(27) =27380416404a(28) =54760832916a(29) =109521665940