Sum of solutions of phi(x) = 2^n.

Terms

a(0) =3a(1) =13a(2) =35a(3) =105a(4) =231a(5) =581a(6) =1315a(7) =3225a(8) =6711a(9) =15221a(10) =32755a(11) =74505a(12) =154407a(13) =339397a(14) =718115a(15) =1589145a(16) =3243831a(17) =6946421a(18) =14482675a(19) =31259145a(20) =63894567a(21) =135588037a(22) =281203235a(23) =601400985a(24) =1219907127a(25) =2557715317a(26) =5267017715a(27) =11123540745a(28) =22600784679a(29) =47205887429