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%I #10 Apr 15 2015 16:52:03
%S 2,4,6,7,8,10,12,13,14,16,18,19,20,22,23,24,25,26,28,30,31,32,33,34,
%T 36,37,38,40,41,42,43,44,46,47,48,49,50,52,53,54,55,56,58,59,60,61,62,
%U 63,64,66,67,68,70,71,72,73,74,75,76,77,78,79,80,82,83,84,85,86,88,89,90
%N Numbers n such that n+2 is not a Chen prime.
%C Contains all strictly positive even numbers A005843.
%C For each odd k>1 we can accumulate the numbers == k^2-2 (mod 2k) in a row, the last entry equal to A073577(k):
%C 7; (k=3)
%C 13, 23; (k=5)
%C 19, 33, 47; (k=7)
%C 25, 43, 61, 79; (k=9)
%C 31, 53, 75, 97, 119; (k=11)
%C 7, 63, 89, 115, 141, 167; (k=13)
%C 43, 73, 103, 133, 163, 193,223; (k=17)
%C 49, 83, 17, 151,185, 219, 253, 287; (k=19)
%C Each element T of this table has the format T= k^2-2-j*2*k, so T+2 is of the form k*(k-2*j), therefore not prime, and consequently all elements T are in the sequence.
%Y Cf. A109611, A040976, A073577, A067076.
%K nonn
%O 1,1
%A _Vincenzo Librandi_, Dec 20 2008
%E Edited, 41, 59 (see A102540) etc. inserted by _R. J. Mathar_, Oct 16 2009
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