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A260959
Numbers n such that n is the average of four consecutive primes n-13, n-1, n+1 and n+13.
1
7950, 10500, 32970, 33330, 34470, 36900, 43050, 66360, 71550, 74610, 87120, 89070, 92400, 94560, 95190, 102000, 104310, 121950, 125790, 133980, 148470, 156900, 160710, 168630, 174930, 182640, 194070, 204600, 206250, 230340, 244380, 246510
OFFSET
1,1
COMMENTS
This is a subsequence of A014574 (average of twin prime pairs), A256753 and A249674 (30n).
LINKS
Eric Weisstein's World of Mathematics, Twin Primes
EXAMPLE
7950 is the average of the four consecutive primes 7937, 7949, 7951, 7963.
10500 is the average of the four consecutive primes 10487, 10499, 10501, 10513.
PROG
(Python)
from sympy import isprime, prevprime, nextprime
for i in range(0, 300001, 2):
.. if isprime(i-1) and isprime(i+1):
....if prevprime(i-1) == i-13 and nextprime(i+1) == i+13 : print (i, end=', ')
(Perl) use ntheory ":all"; say join ", ", map { $_+1 } grep { next_prime($_+2)-$_==14 } grep { $_-prev_prime($_)==12 } @{twin_primes(1e6)}; # Dana Jacobsen, Oct 03 2015
CROSSREFS
Cf. A014574, A077800 (twin primes), A249674, A256753.
Sequence in context: A162010 A023322 A064246 * A316906 A316907 A293623
KEYWORD
nonn
AUTHOR
Karl V. Keller, Jr., Aug 06 2015
STATUS
approved