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A201252 Initial primes in prime septuplets (p, p+2, p+8, p+12, p+14, p+18, p+20) preceding the maximal gaps in A201251. 3
5639, 88799, 284729, 1146779, 8573429, 24001709, 43534019, 87988709, 157131419, 522911099, 706620359, 1590008669, 2346221399, 3357195209, 11768282159, 30717348029, 33788417009, 62923039169, 68673910169, 88850237459, 163288980299, 196782371699, 421204876439 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Prime septuplets (p, p+2, p+8, p+12, p+14, 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 A201251; see more comments there. A233038 lists the corresponding primes at the end of the maximal gaps.

LINKS

Alexei Kourbatov, Table of n, a(n) for n = 1..52

Tony Forbes, Prime k-tuplets

Alexei Kourbatov, Maximal gaps between prime k-tuples

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 83160 between septuplets starting at p=5639 and p=88799 is the very first gap, so a(1)=5639. The gap of 195930 between septuplets starting at p=88799 and p=284729 is a maximal gap - larger than any preceding gap; therefore a(2)=88799. The next gap starts at p=284729 and is again a maximal gap, so a(3)=284729. The next gap is smaller, so it does not contribute to the sequence.

CROSSREFS

Cf. A022010 (prime septuplets p, p+2, p+8, p+12, p+14, p+18, p+20), A201251, A233038.

Sequence in context: A229591 A161193 A022010 * A184080 A234401 A203726

Adjacent sequences:  A201249 A201250 A201251 * A201253 A201254 A201255

KEYWORD

nonn,hard

AUTHOR

Alexei Kourbatov, Nov 28 2011

STATUS

approved

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Last modified April 16 14:51 EDT 2014. Contains 240600 sequences.