A269240 Primes 10k + 7 at the end of the maximal gaps in A269238.

17, 37, 97, 457, 1087, 4787, 10837, 28277, 39607, 61297, 131267, 250687, 425837, 2385587, 2718017, 3208327, 5247757, 6996907, 7402867, 23363807, 27615167, 46360747, 103494877, 118885867, 499145587, 544699457, 705339487, 760950587, 1625987527

Offset

1,1

Comments

Subsequence of A030432.

A269238 lists the corresponding record gap sizes. See more comments there.

Links

Alexei Kourbatov, Table of n, a(n) for n = 1..37

Alexei Kourbatov and Marek Wolf, Predicting maximal gaps in sets of primes, arXiv preprint arXiv:1901.03785 [math.NT], 2019.

Example

The first two primes of the form 10k + 7 are 7 and 17, so a(1)=17. The next prime of this form is 37 and the gap 37-17=20 is a new record, so a(2)=37.

Prog

(PARI) re=0; s=7; forprime(p=17, 1e8, if(p%10!=7, next); g=p-s; if(g>re, re=g; print1(p", ")); s=p)

Crossrefs

Cf. A030432, A269238, A269239.

Sequence in context: A261529 A141886 A350096 * A060429 A052292 A154301

Adjacent sequences: A269237 A269238 A269239 * A269241 A269242 A269243

Keyword

nonn

Author

Alexei Kourbatov, Feb 20 2016

Status

approved