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A122390 Numbers appearing in A122072 at least four times. 2
1327, 8467, 10799, 14107, 15683, 16141, 17257, 19087, 19333, 19609, 20809, 22307, 22573, 22817, 25261, 25471, 28229, 30593, 31397, 31907, 33247, 34061, 34549, 34981, 35617, 35677, 36389, 37747, 37907, 38393, 38461, 38501, 39251, 40289, 40387, 40639, 41299, 43331, 43801 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

19609 is first term appearing in A122072 six times.

Necessary condition: p is followed by a prime gap of at least 32. Sufficient condition: p is followed by a prime gap of at least 40. [Charles R Greathouse IV, Feb 26 2012]

LINKS

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

FORMULA

a(n) ~ n log n since this sequence contains almost all primes. [Charles R Greathouse IV, Feb 26 2012]

PROG

(PARI) p=2; forprime(q=3, 1e5, if(q\10-p\10>3, print1(p", ")); p=q) \\ Charles R Greathouse IV, Feb 26 2012

CROSSREFS

Cf. A122091, A122072.

Sequence in context: A015162 A075037 A134116 * A075038 A082889 A109568

Adjacent sequences:  A122387 A122388 A122389 * A122391 A122392 A122393

KEYWORD

nonn

AUTHOR

Zak Seidov, Oct 19 2006

EXTENSIONS

a(11)-a(39) from Charles R Greathouse IV, Feb 26 2012

STATUS

approved

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Last modified March 7 14:00 EST 2021. Contains 341886 sequences. (Running on oeis4.)