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%I #26 Sep 17 2014 15:53:06
%S 19,920,2869,4704,8125,10194,10939,17588,22661,29856,31178,31779,
%T 53624,59035,61931,66944,72104,81247,91456,98840,103631,106187,117959,
%U 123535,131824,133446,168209,184888,189389,214743,215352,218421,218799,227088,237917,245854
%N Numbers n such that A242720(n) = prime(n)*(prime(n)+4)+3 and A242719(n) - A242720(n) = 2*(prime(n)-1).
%C The sequence is infinite if there are infinitely many primes p_n such that p_n+4, p_n+6, p_n*(p_n+4)+2, p_n*(p_n+6)-2 are primes, but p_n^2-2 is not prime.
%C If the sequence A246748 is also infinite, then these two sequences show that the difference A242720(n) - A242719(n) changes its sign infinitely many times.
%H Peter J. C. Moses, <a href="/A247279/b247279.txt">Table of n, a(n) for n = 1..5000</a>
%F Intersection of A245363 and A247280.
%e If n=920, prime(920)=7207, we have A242720(920) = 7207*7211+3 = 51969680 and A242919(920) - A242920(920) = 51984092 - 51969680 = 14412 = 2*(prime(920)-1).
%Y Cf. A242719, A242720, A242847, A246748.
%K nonn
%O 1,1
%A _Vladimir Shevelev_ and _Peter J. C. Moses_, Sep 11 2014
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