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%I #27 Apr 03 2023 10:36:12
%S 0,1,2,4,5,6,11,18,20,28,70,106,208,726,910,2906,7431,14073,22394,
%T 41422,82587,85461,356981
%N Record values in A194591.
%C Indices of records are given by A217892.
%D Wilfrid Keller, personal communication, 2010.
%H Chris K. Caldwell, The List of Largest Known Primes, <a href="https://t5k.org/primes/page.php?id=107">1355477231 * 2^356981 + 1</a>
%H Carlos Rivera, <a href="http://www.primepuzzles.net/problems/prob_030.htm">Problem 30</a>
%e A194591(59) = 5 since A194591(109) = 6 is the next record value.
%t l = -1; Flatten[Table[k = 0; While[! PrimeQ[n*2^k - 1] && ! PrimeQ[n*2^k + 1], k++]; If[k > l, l = k, {}], {n, 10^5}]] (* _Arkadiusz Wesolowski_, Sep 04 2011 *)
%Y Cf. A194591, A194603, A194606, A194607, A194608, A194635, A194636, A194637, A194638, A194639.
%Y Cf. A103963, A103964, A076335, A180247.
%K more,nonn
%O 1,3
%A _Arkadiusz Wesolowski_, Aug 30 2011
%E a(23)=A194637(22) from Wilfrid Keller, added by _Max Alekseyev_, Oct 18 2014