a(n) = 2^phi(n) + phi(n).

Terms

a(0) =3a(1) =3a(2) =6a(3) =6a(4) =20a(5) =6a(6) =70a(7) =20a(8) =70a(9) =20a(10) =1034a(11) =20a(12) =4108a(13) =70a(14) =264a(15) =264a(16) =65552a(17) =70a(18) =262162a(19) =264a(20) =4108a(21) =1034a(22) =4194326a(23) =264a(24) =1048596a(25) =4108a(26) =262162a(27) =4108a(28) =268435484a(29) =264