%I #2 Dec 09 2007 03:00:00
%S 15,27,45,51,63,85,95,99,111,119,123,125,153,165,175,187,189,195,207,
%T 219,221,231,243,245,255,297,315,325,335,363,365,387,399,411,429,435,
%U 441,447,455,483,485,495,507,511,561,585,603,621,627,629,639,645,655
%N Odd integers that are nonprime, such that there exist two factors of each number that when multiplied together in binary base, do not ever require the use of a "carry" bit.
%e 45 = 5*9:
%e ....1001.(9)
%e ...*.101.(times.5)
%e .-------
%e ....1001
%e ...00000
%e ..100100
%e .-------
%e ..101101.(=45)
%e No carry bit needed!
%K base,easy,nonn
%O 0,1
%A Paul Klemstine (paulklemstine(AT)yahoo.com), Sep 29 2005
|