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A163112 Prime numbers with gaps larger than 20 towards both neighboring primes. 1
16033, 16787, 18013, 23719, 24281, 29101, 32749, 33247, 33679, 33997, 37747, 38501, 40063, 40387, 42533, 42611, 44417, 46957, 51109, 51383, 53479, 54217, 55291, 55763, 56333, 56569, 58271, 58511, 58831, 59833, 61441, 61781, 62273 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Subsequence of A163111.

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..10000

Index entries for primes, gaps between

FORMULA

{A000040(i) : A001223(i) > 20 and A001223(i-1) > 20}. - R. J. Mathar, Jul 27 2009

MAPLE

p := 2; q := 3; r := 3; for n from 2 to 15000 do if q-p > 20 and r-q > 20 then printf("%d, ", q) ; fi; p := q; q := r; r := nextprime(r) ; od: # R. J. Mathar, Jul 27 2009

MATHEMATICA

lst={}; Do[p=Prime[n]; If[ !PrimeQ[p-2]&&!PrimeQ[p+2]&&!PrimeQ[p-4]&&!PrimeQ[p+4]&&!PrimeQ[p-6]&&!PrimeQ[p+6]&&!PrimeQ[p-8]&&!PrimeQ[p+8]&&!PrimeQ[p-10]&&!PrimeQ[p+10]&&!PrimeQ[p-12]&&!PrimeQ[p+12]&&!PrimeQ[p-14]&&!PrimeQ[p+14]&&!PrimeQ[p-16]&&!PrimeQ[p+16]&&!PrimeQ[p-18]&&!PrimeQ[p+18]&&!PrimeQ[p-20]&&!PrimeQ[p+20], AppendTo[lst, p]], {n, 8!}]; lst

Select[Partition[Prime[Range[7000]], 3, 1], Min[Differences[#]]>20&] [[All, 2]] (* Harvey P. Dale, Mar 16 2017 *)

CROSSREFS

Cf. A137875, A137874, A137873, A137872, A137871, A163111.

Sequence in context: A151877 A187854 A204942 * A202420 A031839 A062674

Adjacent sequences:  A163109 A163110 A163111 * A163113 A163114 A163115

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, Jul 20 2009

EXTENSIONS

Definition rephrased by R. J. Mathar, Jul 27 2009

STATUS

approved

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Last modified November 29 13:17 EST 2021. Contains 349416 sequences. (Running on oeis4.)