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A240569 Primes of the form k(m) + k(m+2) where k(m) = A018252(m) (nonprimes), m >= 1.

%I A240569 #26 Sep 08 2022 08:46:07
%S A240569 7,47,73,107,157,167,179,193,227,263,313,347,421,467,503,587,613,661,
%T A240569 673,719,733,757,877,887,983,997,1019,1093,1153,1187,1213,1307,1367,
%U A240569 1381,1439,1453,1487,1523,1753,1823,1873,1907,1933,1993,2017,2027,2137,2207,2341,2447,2473,2593,2797
%N A240569 Primes of the form k(m) + k(m+2) where k(m) = A018252(m) (nonprimes), m >= 1.
%C A240569 This sequence gives the increasingly ordered primes of the form k(m) + k(m+2) with k(m) = A018252(m). The m values are 1, 14, 24, 37, 56, 60, ...
%H A240569 Harvey P. Dale, <a href="/A240569/b240569.txt">Table of n, a(n) for n = 1..1000</a>
%e A240569 a(1) = 7 is the smallest prime of the mentioned form, obtained for m=1: A018252(1) + A018252(3) = 1 + 6 = 7.
%e A240569 a(2) = 47 is the second smallest prime of this form, with m = 14:  A018252(14) + A018252(16) = 22 + 25 = 47.
%t A240569 Module[{nps=With[{nn=2000},Complement[Range[nn],Prime[Range[PrimePi[ nn]]]]]},Select[ #[[1]]+#[[3]]&/@Partition[nps,3,1],PrimeQ]] (* _Harvey P. Dale_, Dec 12 2021 *)
%o A240569 (Magma) m:=1500; NonPrime:=[i: i in [0..m] | not IsPrime(i)]; [q: n in [2..#NonPrime-1] | IsPrime(q) where q is NonPrime[n-1]+NonPrime[n+1]];
%Y A240569 Cf. A018252, A167611.
%K A240569 nonn,easy
%O A240569 1,1
%A A240569 _Ilya Lopatin_ and _Juri-Stepan Gerasimov_, Apr 08 2014
%E A240569 Edited by _Wolfdieter Lang_, Apr 11 2014