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A098039

Numbers p such that p = (prime(n)+ prime(n+3))/2 is prime for prime indices n=2, 3, 5...
(history; published version)

#4 by N. J. A. Sloane at Tue Oct 01 17:58:04 EDT 2013

AUTHOR

_Cino Hilliard (hillcino368(AT)gmail.com), _, Sep 10 2004

Discussion

Tue Oct 01

17:58

OEIS Server: https://oeis.org/edit/global/1955

#3 by N. J. A. Sloane at Wed Dec 06 03:00:00 EST 2006

KEYWORD

easy,nonn,new

AUTHOR

Cino Hilliard (hillcino368(AT)hotmailgmail.com), Sep 10 2004

#2 by N. J. A. Sloane at Tue Jul 19 03:00:00 EDT 2005

NAME

Numbers p such that p = (prime(n)+ prime(n+3))/2 is prime for prime indices n=2, 3, 5... .

KEYWORD

easy,nonn,new

#1 by N. J. A. Sloane at Wed Sep 22 03:00:00 EDT 2004

NAME

Numbers p such that p = (prime(n)+ prime(n+3))/2 is prime for prime indices n=2, 3, 5... .

DATA

7, 23, 37, 47, 73, 809, 1453, 1931, 2621, 3571, 3917, 4793, 7901, 8819, 9467, 10181, 11657, 12421, 12659, 12781, 13229, 14449, 17383, 21739, 22079, 24151, 26501, 28663, 30881, 32749, 33353, 34439, 38083, 38501, 42467, 42703, 43397, 48091

OFFSET

2,1

EXAMPLE

prime(7)+ prime(10) = 17+29. 46/2 = 23, the second term in the table.

PROG

(PARI) g(n, m) = forprime(x=1, n, y=(prime(x)+prime(x+m)); if(y%2==0&isprime(y/2), print1(y\2", ")))

KEYWORD

easy,nonn,new

AUTHOR

Cino Hilliard (hillcino368(AT)hotmail.com), Sep 10 2004

STATUS

approved