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Composites of the form ((x+y)/3+2)/(x-y), where x and y are prime.
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%I #7 Mar 30 2012 18:52:25

%S 4,8,12,14,18,22,28,33,38,39,52,64,74,77,78,82,84,108,113,124,129,138,

%T 143,144,147,148,152,162,169,182,183,203,214,217,218,238,242,248,249,

%U 259,262,264,267,278,298,312,333,334,348,357,368,374,392,399,407,413

%N Composites of the form ((x+y)/3+2)/(x-y), where x and y are prime.

%e If x=23 and y=19, then ((23+19)/3+2)/(23-19)=16/4=4=a(1).

%e If x=47 and y=43, then ((47+43)/3+2)/(47-43)=32/4=8=a(2).

%e If x=71 and y=67, then ((71+67)/3+2)/(71-67)=48/4=12=a(3).

%e If x=83 and y=79, then ((83+79)/3+2)/(83-79)=72/4=18=a(4).

%e If x=107 and y=103, then ((107+1103)/3+2)/(107-103)=88/4=22=a(5).

%e If x=131 and y=127, then ((131+127)/3+2)/(131-127)=112/4=28=a(6),

%e etc.

%Y Cf. A000040, A002808, A141468.

%K nonn,less

%O 1,1

%A _Juri-Stepan Gerasimov_, Aug 28 2008

%E Corrected omission in Examples section. - Dan Graham (dan.a.graham(AT)hotmail.co.uk), Apr 11 2010