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%I #12 Nov 30 2020 04:00:10
%S 4,46,74,94,106,134,158,166,178,194,226,254,262,314,326,334,346,422,
%T 446,466,502,514,526,529,554,586,614,634,662,674,706,718,734,746,758,
%U 766,778,794,802,818,851,878,886,898,914,934,958,974,982,998,1006,1018,1081
%N Numbers that are the products of two single (or isolated or non-twin) primes.
%H Amiram Eldar, <a href="/A176312/b176312.txt">Table of n, a(n) for n = 1..10000</a>
%p isA007510 := proc(n) isprime(n) and not isprime(n+2) and not isprime(n-2) ; simplify(%) ; end proc:
%p isA176312 := proc(n) for d in numtheory[divisors](n) do if isA007510(d) and isA007510(n/d) then return true; end if; end do: return false; end proc:
%p for n from 1 to 1200 do if isA176312(n) then printf("%d,",n) ; end if; end do: # _R. J. Mathar_, Apr 20 2010:
%t Select[Range[1000], PrimeOmega[#] == 2 && AllTrue[FactorInteger[#][[;;, 1]], ! PrimeQ[#1 - 2] && ! PrimeQ[#1 + 2] &] &] (* _Amiram Eldar_, Nov 30 2020 *)
%Y Cf. A007510.
%K nonn
%O 1,1
%A _Juri-Stepan Gerasimov_, Apr 15 2010
%E Entries checked by _R. J. Mathar_, Apr 20 2010
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