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A268929
Primes 6k - 1 preceding the maximal gaps in A268928.
4
5, 29, 113, 197, 521, 1109, 1733, 6389, 7349, 35603, 148517, 180797, 402593, 406907, 2339039, 5521721, 11157989, 20831267, 22440701, 27681263, 73451723, 241563407, 953758109, 1444257671, 1917281213, 6822753629, 15867286361, 28265029631, 40841579819, 177858259463
OFFSET
1,1
COMMENTS
Subsequence of A007528 and A334544.
A268928 lists the corresponding record gap sizes. See more comments there.
LINKS
Alexei Kourbatov and Marek Wolf, Predicting maximal gaps in sets of primes, arXiv preprint arXiv:1901.03785 [math.NT], 2019.
FORMULA
a(n) = A268930(n) - A268928(n). - Alexei Kourbatov, Jun 15 2020.
EXAMPLE
The first two primes of the form 6k-1 are 5 and 11, so a(1)=5. The next primes of this form are 17, 23, 29; the gaps 17-11 = 23-17 = 29-23 are not records so nothing is added to the sequence. The next prime of this form is 41 and the gap 41-29=12 is a new record, so a(2)=29.
PROG
(PARI) re=0; s=5; forprime(p=11, 1e8, if(p%6!=5, next); g=p-s; if(g>re, re=g; print1(s", ")); s=p)
CROSSREFS
KEYWORD
nonn
AUTHOR
Alexei Kourbatov, Feb 15 2016
STATUS
approved