Finite(?) Sequence (involving divisors)

hv at hv at
Wed Oct 31 13:20:48 CET 2007

say n = m^2, then we have n divisible by m^2(m-1), so we require m-1 = 1.
square root being non-isolated.
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From: Brendan McKay <bdm at>
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Subject: Question about names of sequences
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What is the policy about changing names of sequences?

I have in mind A001121 = "Number of skew digraphs in switching classes
of Hadamard matrices of order 4n."

Nobody calls them skew digraphs any more (I'm not even sure that
they were called that at all past the original paper).  The modern
name would be "Number of doubly-regular tournaments of order 4n-1".

But, should names of sequences be changed like that, especially
very early sequences?


The name line often gets changed, esp. if the original
one was a short one from the punched cards days

i'll fix that one in some way

thanks for the suggestion!


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