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%I #4 Apr 28 2018 14:52:33
%S 15,22,34,35,39,58,86,87,94,95,119,123,134,142,143,146,159,178,202,
%T 203,206,214,215,218,219,254,299,302,303,327,335,382,394,395,446,447,
%U 454,482,502,515,527,538,543,554,566,623,634,635,695,698,699,707,718,746
%N Semiprimes equal to p*q + 1, where p and q are distinct primes.
%t With[{nn=60},Take[Select[Union[Times@@#+1&/@Subsets[Prime[Range[2nn]],{2}]],PrimeOmega[#]==2&],nn]] (* _Harvey P. Dale_, Apr 28 2018 *)
%o (PARI) for(i=1,1000,if(bigomega(i)==2&&bigomega(i+1)==2&&issquare(i)==0,print1(i+1,","))) (Klasen)
%Y Cf. A109287, A109289, A109290.
%K nonn
%O 1,1
%A _Giovanni Teofilatto_, Aug 20 2005
%E More terms from Lambert Klasen (lambert.klasen(AT)gmx.net), Aug 21 2005
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