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A233425 Primes p in prime septuplets (p, p+2, p+6, p+8, p+12, p+18, p+20) at the end of the maximal gaps in A201051. 3
165701, 1068701, 11900501, 39431921, 67816361, 124716071, 300768311, 428319371, 661972301, 1346761511, 1699221521, 3205239881, 10540522241, 16206106991, 23911479071, 38749334621, 159330579041, 351146640191, 383960791211, 714031248641, 2881987944371, 3381911721101, 5105053487531 (list; graph; refs; listen; history; text; internal format)



Prime septuplets (p, p+2, p+6, p+8, p+12, p+18, p+20) are one of the two types of densest permissible constellations of 7 primes. Maximal gaps between septuplets of this type are listed in A201051; see more comments there.


Alexei Kourbatov, Table of n, a(n) for n = 1..36

Tony Forbes, Prime k-tuplets

Alexei Kourbatov, Maximal gaps between prime septuplets

Alexei Kourbatov, Tables of record gaps between prime constellations, arXiv preprint arXiv:1309.4053, 2013.

Eric W. Weisstein, k-Tuple Conjecture


The gap of 165690 between septuplets starting at p=11 and p=165701 is the very first gap, so a(1)=165701. The gap of 903000 between septuplets starting at p=165701 and p=1068701 is a maximal (record) gap - larger than any preceding gap; therefore a(2)=1068701. The next gap of 10831800 ending at p=11900501 is again a record, so a(3)=11900501. The next gap is smaller, so a new term is not added to the sequence.


Cf. A022009, A201051, A201249.

Sequence in context: A233701 A224582 A201051 * A183834 A203274 A061741

Adjacent sequences:  A233422 A233423 A233424 * A233426 A233427 A233428




Alexei Kourbatov, Dec 09 2013



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Last modified October 22 21:52 EDT 2014. Contains 248411 sequences.