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%I #7 Apr 03 2023 10:36:13
%S 2,2,2,2,47,3,53,677,823,227,1907,1103,17,163,2693,1213,277,2767,887,
%T 8353,1013,773,6967,1423,2593,9643,157,18013,263,2137,2837,107,3467,
%U 2137,17,2777,1453,2683,7963,3517,2767,53527,8563,227,367,27673,30853,5087,7723,14753,41687,137,48647,26357,16747,2797,9887,35933
%N Least prime p such that p*6^n +/- 1 are primes.
%C a(1) >= A064215(n). First n's such that a(n) = A064215(n): 2, 3, 4, 6, 13, 27, 29, 32, 35, 40, 44, 45, 52, 60, 67, 71, 79, 86, 87, 97, 99.
%C According to Dickson's Conjecture a(n) exists for any n.
%H Chris Caldwell, <a href="https://t5k.org/glossary/xpage/DicksonsConjecture.html">Prime Glossary: Dickson's Conjecture</a>
%t Table[ n6=6^n; p = 2; While[ ! PrimeQ[q = p*n6 + 1 ] || ! PrimeQ[ q - 2 ], p = NextPrime[p] ]; p, {n, 100}]
%Y Cf. A064215 (least k: k*6^n +/- 1 are primes).
%K nonn
%O 1,1
%A _Zak Seidov_, Apr 26 2013