A023286 -id:A023286 - cp's OEIS frontend

A023316 Primes that remain prime through 4 iterations of function f(x) = 5x + 8.

7, 43, 883, 2269, 2917, 7621, 15541, 15937, 36541, 38113, 54787, 60961, 67033, 71359, 77491, 79693, 82531, 84967, 112621, 129589, 176461, 185683, 192547, 239671, 248071, 267373, 271489, 271549, 310231, 316471, 340957, 343267, 350617, 382303

Offset: 1

David W. Wilson

nonn

Primes p such that 5*p+8, 25*p+48, 125*p+248 and 625*p+1248 are also primes. - Vincenzo Librandi, Aug 04 2010

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

Subsequence of A023220, A023255, A023286, and A111225.

[n: n in [1..1000000] | IsPrime(n) and IsPrime(5*n+8) and IsPrime(25*n+48) and IsPrime(125*n+248) and IsPrime(625*n+1248)] // Vincenzo Librandi, Aug 04 2010

is(n)=isprime(n) && isprime(5*n+8) && isprime(25*n+48) && isprime(125*n+248) && isprime(625*n+1248) \\ Charles R Greathouse IV, Oct 08 2016

a(n) == 1 or 19 (mod 42) for n > 1. - John Cerkan, Oct 07 2016

A023344 Primes that remain prime through 5 iterations of function f(x) = 5x + 8.

Original entry on oeis.org

7, 7621, 15937, 382933, 462271, 518803, 866941, 1025407, 1142503, 1427347, 1742473, 1980067, 2343619, 2910031, 3015283, 4344121, 4352269, 4544209, 5081893, 5116543, 5127043, 5482531, 5484379, 5501473, 5648221, 6452899, 7213897, 7968469

Offset: 1

David W. Wilson

nonn

Primes p such that 5*p+8, 25*p+48, 125*p+248, 625*p+1248 and 3125*p+6248 are also primes. - Vincenzo Librandi, Aug 05 2010

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

Subsequence of A023220, A023255, A023286, A023316, and A111225.

[n: n in [1..10000000] | IsPrime(n) and IsPrime(5*n+8) and IsPrime(25*n+48) and IsPrime(125*n+248) and IsPrime(625*n+1248) and IsPrime(3125*n+6248)] // Vincenzo Librandi, Aug 05 2010

Select[Prime[Range[550000]],And@@PrimeQ[NestList[5#+8&,#,5]]&] (* Harvey P. Dale, Jun 04 2011 *)

a(n) == 19 (mod 42) for n > 1. - John Cerkan, Oct 22 2016

cp's OEIS Frontend

A023316 Primes that remain prime through 4 iterations of function f(x) = 5x + 8.

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