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%I #5 Dec 29 2023 10:35:14
%S 91,115,121,205,295,301,319,325,391,403,451,481,511,535,667,685,701,
%T 721,745,763,775,799,841,847,865,871,895,913,931,955,961,985,1003,
%U 1075,1111,1135,1195,1207,1243,1267,1309,1333,1339,1345,1351,1375,1387,1411,1417
%N Composites of the form (3*x*y-y-6)/(3*x+1), where x=composite and y=composite.
%C x=c(i)=i-th composite and y=c(j)=j-th composite.
%e If x=16 and y=95, then
%e (3*16*95-95-6)/(3*16+1)=4459/49=91=a(1).
%e If x=20 and y=119, then (3*20*119-119-6)/(3*20+1)=7015/61=115=a(2).
%e If x=21 and y=125, then (3*21*125-125-6)/(3*21+1)=7744/64=121=a(3).
%e If x=35 and y=209, then (3*35*209-209-6)/(3*35+1)=21730/106=205=a(4).
%e If x=50 and y=299, then (3*50*299-299-6)/(3*50+1)=44545/151=295=a(5).
%e If x=51 and y=305, then (3*51*305-305-6)/(3*51+1)=46354/154=301=a(6),
%e etc.
%Y Cf. A002808, A000040.
%K nonn
%O 1,1
%A _Juri-Stepan Gerasimov_, Aug 28 2008
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