A072511 & A121516

zak seidov zakseidov at yahoo.com
Sun Sep 10 18:43:04 CEST 2006


Seqfans,

Except for the first term in A072511,
are A121516 = A072511?
Thanks, Zak

%I A072511
%S A072511
1,4,8,12,18,24,30,39,42,45,57,72,60,84,90,117,123,
%N A072511 Let f(x) = A061357(x) be the number of
primes p < x such that 2x-p is also prime. 
               a(n) is the smallest positive integer x
such that f(x) = n.

%I A121516
%S A121516
4,8,12,18,24,30,39,42,45,57,72,60,84,90,117,123,
%N A121516 Least number m such that 2m can be
expressed as the sum of two distinct primes by 
               exactly n ways.


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