Numbers n such that the Phi_n(2) is the product of exactly two primes and is divisible by 2n+1.

Terms

a(0) =11a(1) =20a(2) =23a(3) =35a(4) =39a(5) =48a(6) =83a(7) =96a(8) =131a(9) =231a(10) =303a(11) =375a(12) =384a(13) =519a(14) =771a(15) =848a(16) =1400a(17) =1983a(18) =2280a(19) =2640a(20) =2715a(21) =3359a(22) =6144a(23) =7736a(24) =7911a(25) =11079a(26) =13224a(27) =16664a(28) =24263a(29) =36168