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A138695 Primes p such that 24*p-1, 24*p+1 and 30*p-1, 30*p+1 are twin primes. 1
43, 113, 9283, 13147, 14057, 17977, 26893, 34273, 47123, 47543, 56477, 60887, 75557, 123803, 137873, 153623, 163337, 201797, 250307, 284747, 325697, 333787, 349637, 356287, 358597, 447217, 455687, 538943, 561553, 563263, 582317, 616757 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1600

EXAMPLE

24*43-1=1031, 24*43+1=1033; 30*43-1=1289, 30*43+1=1291.

MATHEMATICA

a=24; b=30; Select[Prime[Range[14^4]], PrimeQ[a*#-1]&&PrimeQ[a*#+1]&&PrimeQ[b*#-1]&&PrimeQ[b*#+1]&]

PROG

(MAGMA) [p: p in PrimesUpTo(1000)| IsPrime(24*p-1) and IsPrime(24*p+1) and IsPrime(30*p-1) and IsPrime(30*p+1)]; // Vincenzo Librandi, Nov 24 2010

CROSSREFS

Sequence in context: A039471 A104783 A142081 * A297412 A282294 A251075

Adjacent sequences:  A138692 A138693 A138694 * A138696 A138697 A138698

KEYWORD

nonn,easy

AUTHOR

Vladimir Joseph Stephan Orlovsky, May 15 2008

STATUS

approved

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Last modified November 29 12:16 EST 2020. Contains 338766 sequences. (Running on oeis4.)