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%I #24 Feb 23 2024 20:01:59
%S 15,21,33,35,39,45,51,55,57,63,65,69,75,77,85,87,91,93,95,99,111,115,
%T 117,119,123,129,133,135,141,143,145,147,153,155,159,161,171,175,177,
%U 183,185,187,189,201,203,205,207,209,213,215,217,219,221,225,235,237
%N Odd numbers with exactly 2 distinct prime factors.
%C Numbers of the form p^i*q^j where p, q are distinct odd primes and i>=1, j>=1.
%C Subset of A098905 (which contains in addition A046390 and numbers like 255255, 285285, 345345, 373065 etc.).
%p isA225375 := proc(n) RETURN( (n mod 2 = 1) and (A001221(n) = 2) ); end proc:
%p for n from 1 to 840 do if isA225375(n) then printf("%d,",n) ; end if; end do:
%t Select[2 Range[200] + 1, PrimeNu[#] == 2&] (* _Jean-François Alcover_, Apr 04 2020 *)
%o (PARI) is_A046388(n)={ bittest(n,0) & omega(n)==2 } \\ _M. F. Hasler_, Feb 13 2012
%Y Subsequence of A272592. A046388 is a subsequence.
%Y Cf. A046315, A046390, A046404, A024556, A056913.
%Y Different from A046388, A098905.
%K nonn
%O 1,1
%A _R. J. Mathar_, Oct 13 2008
%E Entry created by _N. J. A. Sloane_, May 09 2013 in order to restore the original definition of A046388.
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