a(n) = 12*2^n + 62.

Terms

a(0) =74a(1) =86a(2) =110a(3) =158a(4) =254a(5) =446a(6) =830a(7) =1598a(8) =3134a(9) =6206a(10) =12350a(11) =24638a(12) =49214a(13) =98366a(14) =196670a(15) =393278a(16) =786494a(17) =1572926a(18) =3145790a(19) =6291518a(20) =12582974a(21) =25165886a(22) =50331710a(23) =100663358a(24) =201326654a(25) =402653246a(26) =805306430a(27) =1610612798a(28) =3221225534a(29) =6442451006