%I A140389
%S A140389 91,115,121,205,295,301,319,325,391,403,451,481,511,535,667,685,701,721,
%T A140389 745,763,775,799,841,847,865,871,895,913,931,955,961,985,1003,1075,1111,
%U A140389 1135,1195,1207,1243,1267,1309,1333,1339,1345,1351,1375,1387,1411,1417
%N A140389 Composites of the form ((3*x*y-y-6)/(3*x+1), where x=composite and y=composite.
%C A140389 x=c(i)=i-th composite and y=c(j)=j-th composite.
%e A140389 If x=16 and y=95, then
%e A140389 ((3*16*95-95-6)/(3*16+1)=4459/49=91=a(1).
%e A140389 If x=20 and y=119, then ((3*20*119-119-6)/(3*20+1)=7015/61=115=a(2).
%e A140389 If x=21 and y=125, then ((3*21*125-125-6)/(3*21+1)=7744/64=121=a(3).
%e A140389 If x=35 and y=209, then ((3*35*209-209-6)/(3*35+1)=21730/106=205=a(4).
%e A140389 If x=50 and y=299, then ((3*50*299-299-6)/(3*50+1)=44545/151=295=a(5).
%e A140389 If x=51 and y=305, then ((3*51*305-305-6)/(3*51+1)=46354/154=301=a(6),
%e A140389 etc.
%Y A140389 Cf. A002808, A000040.
%Y A140389 Sequence in context: A126134 A020223 A161945 this_sequence A157345 A092125
A005935
%Y A140389 Adjacent sequences: A140386 A140387 A140388 this_sequence A140390 A140391
A140392
%K A140389 nonn
%O A140389 1,1
%A A140389 Juri-Stepan Gerasimov (2stepan(AT)rambler.ru), Aug 28 2008
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