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%I #2 Jul 12 2012 00:39:49
%S 15,21,35,39,51,65,95,155,221,329,371,485,519,611,905,989,1121,1199,
%T 1469,1509,1541,1661,1821,3039,3189,3431,3641,3791,4055,4109,4281,
%U 4601,4859,5079,5111,5195,5331,5429,5579,5951,5979,6161,6245,6731,6881,7415
%N an=n-th smallest integer of the form m=p1*p2 where pi are odd primes such that d+2m/d are all primes for d dividing 2m.
%e E.g. 35=5.7, 2.5.7+1=71, 2.5+7=17, 2.7+5=19. 5.7+2=37 are all primes and this is the 3rd such number, so a(3)=35
%Y Cf. A128276, A128277, A128278, A045536.
%K nonn
%O 1,1
%A Kok Seng Chua (chuakokseng(AT)hotmail.com), Mar 05 2007