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A087378 Smallest k such that both k-n and k+n are primes and there are no primes between them. 3

%I #7 Dec 05 2013 19:56:21

%S 2,4,9,26,93,144,205,120,1839,532,897,1140,1681,2490,2985,4312,5607,

%T 1344,9569,30612,19353,16162,15705,81486,28253,31932,19635,35644,

%U 82101,44322,43361,34092,89721,162176,134547,173394,31433,404634,212739

%N Smallest k such that both k-n and k+n are primes and there are no primes between them.

%C For n>0, a(n) = arithmetic mean of the smallest pair of two consecutive primes with a difference 2n.

%F a(n) = A000230(n)+n. - _David Wasserman_, May 24 2005

%e a(5) = 144 as 139 and 149 both are prime and all numbers from 140 to 148 are composite.

%K nonn

%O 0,1

%A _Amarnath Murthy_, Sep 09 2003

%E More terms from _David Wasserman_, May 24 2005

%E Edited by _Franklin T. Adams-Watters_, Oct 26 2006

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Last modified July 25 16:17 EDT 2024. Contains 374612 sequences. (Running on oeis4.)