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%I #10 Jan 17 2019 15:54:49
%S 19,29,269,1129,3779,13499,14969,24989,50599,90749,91639,167449,
%T 421739,435949,527929,623299,1676069,5733929,9690829,31067999,
%U 35901949,40295539,47435809,59135689,156735209,283374709,410704109,603775769,1008309229,1036100939,1639285799
%N Primes 10k + 9 preceding the maximal gaps in A269261.
%C Subsequence of A030433.
%C A269261 lists the corresponding record gap sizes. See more comments there.
%H Alexei Kourbatov, <a href="/A269262/b269262.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 + 9 are 19 and 29, so a(1)=19. The next prime of this form is 59 and the gap 59-29=30 is a new record, so a(2)=29.
%o (PARI) re=0; s=19; forprime(p=29, 1e8, if(p%10!=9, next); g=p-s; if(g>re, re=g; print1(s", ")); s=p)
%Y Cf. A030433, A269261, A269263.
%K nonn
%O 1,1
%A _Alexei Kourbatov_, Feb 20 2016