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Primes of the form n/(2*(prime(n+2) - prime(n+1))).
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%I #6 Oct 04 2015 01:42:33

%S 3,3,3,11,3,17,5,5,11,7,19,43,31,11,29,101,53,67,53,83,43,59,61,101,

%T 43,223,113,239,127,71,101,79,109,53,421,149,467,157,487,509,89,181,

%U 557,577,97,617,647,223,101,79,743

%N Primes of the form n/(2*(prime(n+2) - prime(n+1))).

%C Listed in order of increasing n.

%e For n=12, 12/2/(p(12+2)-p(12+1))=12/2/(43-31)=3=a(1).

%e For n=36, 36/2/(p(36+2)-p(36+1))=36/2/(163-157)=3=a(3).

%p for n from 1 to 3000 do p := n/2/(ithprime(n+2)-ithprime(n+1)) ; if type(p,'integer') then if isprime(p) then printf("%d,",p) ; fi; fi; od: # _R. J. Mathar_, Aug 03 2009

%Y Cf. A000040, A001223.

%K nonn

%O 1,1

%A _Juri-Stepan Gerasimov_, Sep 15 2008

%E Definition, examples and terms corrected by _R. J. Mathar_, Aug 03 2009