login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A201249 Initial primes in prime septuplets (p, p+2, p+6, p+8, p+12, p+18, p+20) preceding the maximal gaps in A201051. 3
11, 165701, 1068701, 25658441, 45002591, 93625991, 257016491, 367438061, 575226131, 1228244651, 1459270271, 2923666841, 10180589591, 15821203241, 23393094071, 37846533071, 158303571521, 350060308511, 382631592641, 711854781551, 2879574595811, 3379186846151 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

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.

LINKS

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

EXAMPLE

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

CROSSREFS

Cf. A022009 (prime septuplets p, p+2, p+6, p+8, p+12, p+18, p+20), A201051, A233425.

Sequence in context: A116622 A013794 A022009 * A144837 A085017 A239203

Adjacent sequences:  A201246 A201247 A201248 * A201250 A201251 A201252

KEYWORD

nonn,hard

AUTHOR

Alexei Kourbatov, Nov 28 2011

STATUS

approved

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

Content is available under The OEIS End-User License Agreement .

Last modified October 24 14:55 EDT 2014. Contains 248516 sequences.