%I #18 Oct 17 2016 16:08:39
%S 6,6,4,2,6,2,4,6,4,2,4,2,6,2,4,6,2,4,4,2,4,2,2,4,6,6,4,2,2,2,2,2,4,4,
%T 2,6,2,2,2,6,2,4,2,4,4,2,4,2,6,2,2,2,6,6,2,2,2,2,4,2,2,2,2,4,6,4,2,6,
%U 2,2,2,4,2,4,2,4,2,6,2,4,6,2,2,2,4,2,2,2,2,2,4,6,4,2,2,2,2,2,4,2,4,2,2,2,6
%N First differences of A071904 (Odd composite numbers).
%C Are all terms <=6?
%C This is A067970 without its first term. [From _R. J. Mathar_, Aug 17 2009]
%C Yes, all terms are at most 6. For a value of 8, we have to have p, p+2, p+4 all prime, and this is possible only for p=3. As a result, 1 would have to be an odd composite number, which it is not. Therefore all terms are <=6. [From _J. Lowell_, Aug 17 2009]
%Y A071904
%K nonn
%O 1,1
%A _Zak Seidov_, Aug 14 2009
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