Numbers in A206853 without proper divisors > 1 from the same sequence.

Terms

a(0) =1a(1) =2a(2) =7a(3) =11a(4) =13a(5) =31a(6) =47a(7) =59a(8) =61a(9) =127a(10) =191a(11) =223a(12) =239a(13) =251a(14) =895a(15) =991a(16) =1007a(17) =1019a(18) =1021a(19) =2047a(20) =3071a(21) =3583a(22) =3967a(23) =4031a(24) =4079a(25) =4091a(26) =4093a(27) =8191a(28) =15359a(29) =16127