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%I #21 May 19 2021 00:22:23
%S 140,4572,1082,816,11885,13796,177,27187,31169,171594,98856,120624,
%T 872929,4973720,351333
%N First differences of values of n for Cullen primes in A005849.
%C Carlos Rivera's Problem 50 is devoted to this topic. If we pair differences according to magnitude, we first obtain 177-140=37 a prime. This raises the question as to whether there are other such prime values.
%H Carlos Rivera, <a href="https://www.primepuzzles.net/problems/prob_050.htm">Problem 50. Is there a Cullen prime Cn with n prime?</a>, The Prime Puzzles and Problems Connection.
%F a(n) = A005849(n+1) - A005849(n). - _Michel Marcus_, Sep 27 2020
%e a(1)=140 because the first pair of n are 1 and 141. 141 - 1 = 140.
%Y Cf. A005849, A128194.
%K nonn,more
%O 1,1
%A _Enoch Haga_, Feb 18 2007
%E Offset 1 from _Michel Marcus_, Sep 27 2020
%E a(14)-a(15) added by _Florian Baur_, Sep 27 2020
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