A157976 -id:A157976 - cp's OEIS frontend

A157978 Primes p such that 4*p - 3 is also a prime.

2, 5, 11, 19, 23, 29, 59, 61, 71, 79, 89, 101, 103, 109, 113, 131, 149, 151, 191, 193, 233, 239, 263, 283, 313, 331, 353, 359, 373, 389, 401, 431, 439, 479, 499, 521, 523, 541, 569, 571, 599, 619, 631, 653, 659, 673, 683, 701, 709, 739, 743, 751, 761, 773, 829

Offset: 1

Vladimir Joseph Stephan Orlovsky, Mar 10 2009

Vincenzo Librandi, Table of n, a(n) for n = 1..3000

Cf. A136082, A136083, A023213, A023221, A023235, A023240, A157974, A136083, A136084, A136085, A136086, A136087, A089440, A157975, A157976, A157977.

[n: n in [0..2000] | IsPrime(n) and IsPrime(4*n - 3)]; // Vincenzo Librandi, Feb 03 2014

q=3;lst={};Do[p=Prime[n];If[PrimeQ[(q+1)*p-q],AppendTo[lst,p]],{n,6!}];lst
Select[Prime[Range[1000]],PrimeQ[4 # - 3]&] (* Vincenzo Librandi, Feb 03 2014 *)

A157977 Primes p such that 20*p + 19 is also prime.

Original entry on oeis.org

2, 3, 11, 17, 23, 29, 41, 71, 101, 149, 167, 233, 239, 251, 263, 269, 281, 293, 317, 347, 353, 401, 449, 461, 491, 503, 557, 563, 569, 647, 683, 743, 797, 857, 941, 947, 953, 977, 1019, 1031, 1091, 1103, 1151, 1163, 1193, 1217, 1283, 1289, 1319, 1361, 1373

Offset: 1

Vladimir Joseph Stephan Orlovsky, Mar 10 2009

Vincenzo Librandi, Table of n, a(n) for n = 1..2000

Cf. A136082, A136083, A023213, A023221, A023235, A023240, A157974, A136083, A136084, A136085, A136086, A136087, A089440, A157975, A157976.

[n: n in [0..2000] | IsPrime(n) and IsPrime(20*n + 19)]; // Vincenzo Librandi, Feb 03 2014

q=19;lst={};Do[p=Prime[n];If[PrimeQ[(q+1)*p+q],AppendTo[lst,p]],{n,6!}];lst
Select[Prime[Range[250]],PrimeQ[20#+19]&] (* Harvey P. Dale, Jul 04 2011 *)

cp's OEIS Frontend

A157978 Primes p such that 4*p - 3 is also a prime.

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