This site is supported by donations to The OEIS Foundation.



Annual Appeal: Please make a donation (tax deductible in USA) to keep the OEIS running. Over 5000 articles have referenced us, often saying "we discovered this result with the help of the OEIS".

(Greetings from The On-Line Encyclopedia of Integer Sequences!)
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



Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy .

Last modified December 5 15:24 EST 2016. Contains 278770 sequences.