A023294 -id:A023294 - cp's OEIS frontend

A023322 Primes that remain prime through 4 iterations of function f(x) = 8x + 7.

7949, 25589, 55799, 61379, 69959, 70229, 74609, 174569, 188369, 204719, 220469, 225629, 233759, 250919, 286619, 363659, 552749, 592139, 658349, 735419, 783269, 827549, 931949, 1018889, 1065839, 1126319, 1132739, 1187939, 1215629, 1378529

Offset: 1

David W. Wilson

nonn

Primes p such that 8*p+7, 64*p+63, 512*p+511 and 4096*p+4095 are also primes. - Vincenzo Librandi, Aug 04 2010

John Cerkan, Table of n, a(n) for n = 1..10000

Subsequence of A023231, A023263, A023294, and A139487.

[n: n in [1..5000000] | IsPrime(n) and IsPrime(8*n+7) and IsPrime(64*n+63) and IsPrime(512*n+511) and IsPrime(4096*n+4095)] // Vincenzo Librandi, Aug 04 2010

rp4Q[p_]:=AllTrue[Rest[NestList[8#+7&,p,4]],PrimeQ]; Select[Prime[Range[110000]],rp4Q] (* Harvey P. Dale, Aug 03 2023 *)

a(n) == 9 (mod 10). - John Cerkan, Oct 08 2016

A023350 Primes that remain prime through 5 iterations of function f(x) = 8x + 7.

Original entry on oeis.org

25589, 220469, 225629, 286619, 783269, 1215629, 1407389, 1542029, 1642919, 2329469, 2776979, 3104159, 4082759, 4229129, 5405999, 5905619, 6548849, 6862859, 7681409, 7904669, 8623799, 8971049, 9599309, 9658469, 9725039, 11420579

Offset: 1

David W. Wilson

nonn

Primes p such that 8*p+7, 64*p+63, 512*p+511, 4096*p+4095 and 32768*p+32767 are also primes. - Vincenzo Librandi, Aug 05 2010

John Cerkan, Table of n, a(n) for n = 1..10000

Subsequence of A023231, A023263, A023294, A023322, and A139487.

[n: n in [1..19000000] | IsPrime(n) and IsPrime(8*n+7) and IsPrime(64*n+63) and IsPrime(512*n+511) and IsPrime(4096*n+4095) and IsPrime(32768*n+32767)]; // Vincenzo Librandi, Aug 05 2010

i5Q[p_]:=AllTrue[Rest[NestList[8#+7&,p,5]],PrimeQ]; Select[Prime[Range[760000]],i5Q] (* Harvey P. Dale, Jul 05 2025 *)

a(n) == 29 (mod 30). - John Cerkan, Nov 08 2016

cp's OEIS Frontend

A023322 Primes that remain prime through 4 iterations of function f(x) = 8x + 7.

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