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Non-uniquely factorizable OR-numbrals, i.e., numbrals for which there exist more than one different factorizations into irreducible factors (modulo order).
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%I #5 Aug 02 2017 23:47:12

%S 15,30,31,60,62,63,85,95,111,120,123,124,125,126,127,170,175,190,191,

%T 207,222,223,239,240,243,245,246,247,248,250,251,252,253,254,255,340,

%U 341,350,351,367,379,380,381,382,383,399,414,415,443,444,445,446,447

%N Non-uniquely factorizable OR-numbrals, i.e., numbrals for which there exist more than one different factorizations into irreducible factors (modulo order).

%C See A048888 for the definition of OR-numbral arithmetic.

%e 15 is in A067400 since [15] = [3] * [5] = [3]^3 and [3] and [5] are irreducible.

%Y Cf. A003986, A007059, A048888, A067138, A067139, A067398, A067399, A067401.

%K nonn

%O 1,1

%A _Jens Voß_, Jan 24 2002