A128279 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.

15, 21, 35, 39, 51, 65, 95, 155, 221, 329, 371, 485, 519, 611, 905, 989, 1121, 1199, 1469, 1509, 1541, 1661, 1821, 3039, 3189, 3431, 3641, 3791, 4055, 4109, 4281, 4601, 4859, 5079, 5111, 5195, 5331, 5429, 5579, 5951, 5979, 6161, 6245, 6731, 6881, 7415

Offset: 1

Author

Kok Seng Chua (chuakokseng(AT)hotmail.com), Mar 05 2007

Keywords

• nonn

Examples

			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
		

Crossrefs

Cf. A128276, A128277, A128278, A045536.