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%I #7 Jan 19 2019 20:26:27
%S 6,10,22,46,58,106,118,142,178,202,262,298,346,382,466,526,538,718,
%T 778,802,862,898,958,982,1126,1138,1186,1198,1306,1366,1402,1438,1486,
%U 1522,1642,1822,1858,1966,2026,2062,2122,2218,2326,2386,2446,2458,2566,2578
%N Even semiprimes k such that the largest prime factor + 8 is a prime. Also semiprimes k such that k+16 is semiprime.
%p A006530 := proc(n) numtheory[factorset](n) ; max(op(%)) ; end proc: isA166305 := proc(n) if type(n,'even') then if numtheory[bigomega](n) = 2 then isprime(A006530(n)+8) ; else false; end if; else false; end if; end proc: for n from 4 to 3000 by 2 do if isA166305(n) then printf("%d,",n) ; end if; end do: # _R. J. Mathar_, Jan 30 2010
%t Select[2*Range[1500],PrimeOmega[#]==PrimeOmega[#+16]==2&] (* _Harvey P. Dale_, Dec 28 2013 *)
%Y Cf. A108605, A165986.
%K nonn
%O 1,1
%A _Giovanni Teofilatto_, Oct 11 2009
%E Extended by _R. J. Mathar_, Jan 30 2010
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