Numbers n such that phi(n)=2*phi(n-1).

Terms

a(0) =3a(1) =5a(2) =17a(3) =155a(4) =257a(5) =287a(6) =365a(7) =805a(8) =1067a(9) =2147a(10) =3383a(11) =4551a(12) =6107a(13) =7701a(14) =8177a(15) =9269a(16) =11285a(17) =12557a(18) =12971a(19) =16403a(20) =19229a(21) =19277a(22) =20273a(23) =25133a(24) =26405a(25) =27347a(26) =29155a(27) =29575a(28) =35645a(29) =36419