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A031938 Lower prime of a difference of 20 between consecutive primes. 12
887, 1637, 3089, 3413, 3947, 5717, 5903, 5987, 6803, 7649, 8243, 8543, 8783, 8867, 9257, 10223, 10433, 10667, 11027, 11093, 11177, 11447, 11597, 11657, 11867, 11987, 13127, 13421, 13649, 14087, 14177, 15473, 16943, 17519, 17807 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Remi Eismann, Table of n, a(n) for n = 1..10000

Index entries for primes, gaps between

EXAMPLE

887 is a term as the next prime is 907.

MATHEMATICA

(*M6*) a=887; S={}; Do[b=NextPrime[a]; If[b-a==20, AppendTo[S, a]]; a=b, {10^4}]; S [Zak Seidov, Aug 14 2009]

Transpose[Select[Partition[Prime[Range[2000]], 2, 1], Last[#] - First[#] == 20 &]][[1]] (* Bruno Berselli, Apr 09 2013 *)

PROG

(MAGMA) [p: p in PrimesUpTo(20000) | NextPrime(p)-p eq 20]; // Bruno Berselli, Apr 09 2013

CROSSREFS

Sequence in context: A103811 A190354 A164513 * A165504 A136966 A232152

Adjacent sequences:  A031935 A031936 A031937 * A031939 A031940 A031941

KEYWORD

nonn

AUTHOR

Jeff Burch

EXTENSIONS

Entries and b-file checked by Zak Seidov, Aug 14 2009

STATUS

approved

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Last modified August 21 01:18 EDT 2017. Contains 290855 sequences.