A064981 Numbers k such that k*10^10-1, k*10^10-3, k*10^10-7 and k*10^10-9 are all prime.

13532, 72938, 84614, 118802, 153854, 195725, 233642, 269750, 329621, 425381, 432449, 456401, 488633, 494345, 586346, 628883, 660005, 693500, 702563, 712199, 760196, 804485, 831188, 862790, 981359, 982922, 1040756, 1067657, 1105667

Offset

1,1

Links

Harry J. Smith, Table of n, a(n) for n = 1..100

Mathematica

Select[ Range[2 10^6], PrimeQ[10^10# - 1] && PrimeQ[10^10# - 3] && PrimeQ[10^10# - 7] && PrimeQ[10^10# - 9] &]
Select[Range[111*10^4], AllTrue[10^10 #+{-1, -3, -7, -9}, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Apr 21 2018 *)

Prog

(PARI) { n=0; for (m=1, 10^9, b=10^10*m; if(isprime(b - 1) && isprime(b - 3) && isprime(b - 7) && isprime(b - 9), write("b064981.txt", n++, " ", m); if (n==100, return)) ) } \\ Harry J. Smith, Oct 02 2009

Crossrefs

Sequence in context: A257156 A254738 A342858 * A275370 A204785 A249526

Adjacent sequences: A064978 A064979 A064980 * A064982 A064983 A064984

Keyword

nonn

Author

Robert G. Wilson v, Oct 30 2001

Status

approved