a(n) is the smallest positive integral multiple of 2^n not in the range of the Euler phi function.

Terms

a(0) =3a(1) =14a(2) =68a(3) =152a(4) =304a(5) =608a(6) =1984a(7) =3968a(8) =12032a(9) =24064a(10) =48128a(11) =96256a(12) =192512a(13) =385024a(14) =770048a(15) =1540096a(16) =3080192a(17) =6160384a(18) =12320768a(19) =24641536a(20) =49283072a(21) =98566144a(22) =197132288a(23) =394264576a(24) =788529152a(25) =1577058304a(26) =3154116608a(27) =6308233216a(28) =12616466432a(29) =25232932864