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%I #31 Jan 19 2023 02:58:51
%S 0,1,2,5,6,13,26,65,66,86,114,133,186,294,445,866,1325,1478,1823,2765,
%T 7553,7943,10178,20960,20964,21337,26562,85374,96749,247038
%N Near Cullen numbers: k such that (k+1)*2^k + 1 is prime.
%C Primes in the sequence are 2, 5, 13, 1823, 96749, ... - _R. J. Mathar_, Oct 15 2011
%C We can write (k+1)*2^k + 1 = {(k+1)/2}*4^{(k+1)/2} + 1, and when k is odd, this takes the form of a generalized Cullen prime (base 4). These are listed in A007646. In other words, {2*A007646 - 1} gives all the odd terms of this sequence. - _Jeppe Stig Nielsen_, Oct 16 2019
%H Steven Harvey, <a href="http://harvey563.tripod.com/NearCullen_WoodallPrimes.txt">NearCullen and NearWoodall Primes</a>
%o (PARI) isok(n) = isprime((n+1)*2^n+1); \\ _Michel Marcus_, Nov 09 2013
%Y Cf. A002064, A007646, A230769.
%K nonn,more
%O 1,3
%A _Henri Lifchitz_
%E Corrected and extended by Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 05 2008
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