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%I #10 Jan 17 2019 15:54:30
%S 7,17,67,397,997,4657,10687,28097,39397,61057,130987,250307,425417,
%T 2385157,2717567,3207857,5247257,6996377,7402237,23363167,27614507,
%U 46359967,103494037,118884947,499144627,544698487,705338497,760949557,1625986457
%N Primes 10k + 7 preceding the maximal gaps in A269238.
%C Subsequence of A030432.
%C A269238 lists the corresponding record gap sizes. See more comments there.
%H Alexei Kourbatov, <a href="/A269239/b269239.txt">Table of n, a(n) for n = 1..37</a>
%H Alexei Kourbatov and Marek Wolf, <a href="https://arxiv.org/abs/1901.03785">Predicting maximal gaps in sets of primes</a>, arXiv preprint arXiv:1901.03785 [math.NT], 2019.
%e The first two primes of the form 10k + 7 are 7 and 17, so a(1)=7. The next prime of this form is 37 and the gap 37-17=20 is a new record, so a(2)=17.
%o (PARI) re=0; s=7; forprime(p=17, 1e8, if(p%10!=7, next); g=p-s; if(g>re, re=g; print1(s", ")); s=p)
%Y Cf. A030432, A269238, A269240.
%K nonn
%O 1,1
%A _Alexei Kourbatov_, Feb 20 2016
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