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%I #12 Feb 20 2023 05:19:40
%S 4,10,14,22,26,33,34,35,39,49,55,57,65,74,82,86,87,91,95,106,111,115,
%T 119,121,129,134,142,146,155,158,159,166,169,177,183,187,194,201,205,
%U 209,215,217,219,221,249,254,262,274,278,289,299,301,303,323,326,327,329,339,341
%N Semiprimes m such that either 2m-1 or 2m+1 is prime, but not both.
%e a(1)=4 because 2*4-1=7=prime and 2*4+1=9=nonprime.
%o (PARI) isok(m) = (bigomega(m)==2) && bitxor(isprime(2*m-1), isprime(2*m+1)); \\ _Michel Marcus_, Feb 20 2023
%Y Intersection of A001358 and A174047.
%K nonn
%O 1,1
%A _Juri-Stepan Gerasimov_, Aug 24 2010
%E Corrected (15 removed) by _R. J. Mathar_, Aug 25 2010. Also corrected by _D. S. McNeil_.
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