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A054808
First term of strong prime quintets: p(m+1)-p(m) > p(m+2)-p(m+1) > p(m+3)-p(m+2) > p(m+4)-p(m+3).
4
1637, 1759, 1831, 1847, 1979, 2357, 2447, 2477, 2503, 3413, 3433, 4177, 4493, 5237, 5399, 5419, 6011, 6619, 7219, 7253, 7727, 7853, 7907, 8123, 8467, 9551, 9587, 11003, 11353, 11551, 11813, 12379, 13841, 14797, 15107, 15511, 16007, 16273, 16787, 16993, 17359, 18149, 18289
OFFSET
1,1
COMMENTS
First member of pairs of consecutive primes in A054804 (first of strong quartets): The first 10^4 terms of that sequence yield over 2000 terms of this sequence. - M. F. Hasler, Oct 27 2018
FORMULA
a(n) = prevprime(A054809(n)); A054808 = {m = A054804(n) | nextprime(m) = A054804(n+1)}; nextprime = A151800, prevprime = A151799. - M. F. Hasler, Oct 27 2018
MATHEMATICA
okQ[l_]:=Module[{d=Differences[l]}, d[[1]]>d[[2]]>d[[3]]>d[[4]]]; Transpose[ Select[Partition[Prime[Range[2000]], 5, 1], okQ]][[1]] (* Harvey P. Dale, Aug 15 2011 *)
PROG
(PARI) A054808=List(); for(i=2, 1e4, A054804[i]==A054805[i-1]&&listput(A054808, A054804[i-1])) \\ M. F. Hasler, Oct 27 2018
CROSSREFS
Cf. A051634, A051635; A054800 .. A054803: members of balanced prime quartets (= 4 consecutive primes in arithmetic progression); A054804 .. A054818: members of strong prime quartets, quintets, sextets; A054819 .. A054840: members of weak prime quartets, quintets, sextets, septets.
Sequence in context: A252619 A224461 A233121 * A218010 A298075 A362405
KEYWORD
nonn
AUTHOR
Henry Bottomley, Apr 10 2000
EXTENSIONS
Edited and offset corrected to 1 by M. F. Hasler, Oct 27 2018
STATUS
approved