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%I #9 Jul 31 2017 03:36:21
%S 8,10,14,16,20,22,32,38,40,52,58,68,70,88,110,112,128,130,140,158,178,
%T 182,200,212,238,250,268,292,308,310,338,380,382,410,418,448,488,490,
%U 500,502,520,542,572,578,592,598,632,682,700,718,752,770,772,788,808
%N Integers such that the two adjacent integers are a prime and three times a prime.
%C Union[3*A023208 + 1, 3*A088878 - 1]. [_Zak Seidov_, Aug 07 2009]
%H G. C. Greubel, <a href="/A163628/b163628.txt">Table of n, a(n) for n = 1..10000</a>
%e a(1)=8 which lies between 7=A000040(4) and 9 = A001748(2).
%e a(2)=10 which lies between 9=A001748(2) and 11 = A000040(5).
%t n = 1; A023208 = {}; Do[If[PrimeQ[(Prime[k] - 2 n)/(2 n + 1)], AppendTo[A023208, (Prime[k] - 2 n)/(2 n + 1)]], {k, 1, 1000}]; A023208;
%t A088878 = {}; Do[p = Prime[n]; If[PrimeQ[3*p - 2], AppendTo[A088878, p]], {n, 5!}]; A088878; Union[3*A023208 + 1, 3*A088878 - 1] (* _G. C. Greubel_, Jul 30 2017 *)
%Y Cf. A000040, A163492.
%K nonn
%O 1,1
%A _Juri-Stepan Gerasimov_, Aug 02 2009
%E Many terms like 44, 46, 62 etc. removed by _R. J. Mathar_, Aug 06 2009
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