PRIME6 Erratum


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PRIME6 Erratum



Vapor256@aol.com has found a small oddity in PRIME6. It is not a true "bug",
just something you should be aware of. When PRIME6 factors integers with a very
specific structure, the factor reported may not be the lowest factor. However,
this erratum is pretty minor, because....
The number reported WILL be a factor. (I still believe it will be prime. Am I
right?)
Numbers reported prime are not affected. (They are definitely prime).
It only affects composite numbers with its two lowest prime factors within 210
of each other. (The composite number can have a third or more HIGHER prime
factors).
It only happens when the higher of the two lowest prime factors has the form
(210*N + A) where N is some integer above zero, and A is a number in the list
{121, 143, 169, 187, 209, 1}. It also only happens when the lower prime factor
has the form (210*N + B), where N is that same integer above zero, and B is a
prime number. (I think.) So the amount of numbers affected by this erratum is
very, very small.
It is due to my change in the NTILDE list that saved space. I do not wish to go
back to the old structure, and will release updated documentation. If you wish
to see the bug for yourself, try factoring 431*571 in PRIME6. :-D
S.T.L.
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