

A098029


Primes of the form (prime(n)+ prime(n+3))/2.


2



7, 23, 37, 47, 67, 73, 233, 277, 353, 479, 613, 631, 647, 809, 1097, 1283, 1297, 1433, 1453, 1471, 1493, 1607, 1613, 1663, 1709, 1721, 1783, 1867, 1889, 1901, 1931, 1993, 2099, 2137, 2161, 2377, 2383, 2411, 2521, 2621, 2683, 2693, 2713, 2797, 2879, 3049
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OFFSET

1,1


COMMENTS

The union of {7}, A119381 and A117876.  Irina Gerasimova, Jul 11 2013


LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000


EXAMPLE

prime(2)=3, prime(2+3)=11. (3+11)/2 = 7


MATHEMATICA

Select[(#[[1]]+#[[4]])/2&/@Partition[Prime[Range[500]], 4, 1], PrimeQ] (* Harvey P. Dale, Nov 30 2017 *)


PROG

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


CROSSREFS

Sequence in context: A329931 A157811 A227421 * A098039 A132237 A227064
Adjacent sequences: A098026 A098027 A098028 * A098030 A098031 A098032


KEYWORD

easy,nonn


AUTHOR

Cino Hilliard, Sep 10 2004.


STATUS

approved



