April 1 comes late this year
Richard Guy
rkg at cpsc.ucalgary.ca
Wed Nov 23 19:55:32 CET 2005
When I tried 1, 2, 18, 26 on OEIS I got
no hits, but 1, 3, 8, 9 yielded my full
quota of 30.
Alas, I fear that they are both finite
in the present context, so won't make it
into the Hall of Fame when Neil returns
from his well-earned rest (though I don't
believe that he ever takes one).
They are the integer values of
$\prod_{i=1}^n \frac{\sigma n}{n}$
and the values of n which make this
an integer, where \sigma n is the
sum of divisors function. How did
I come to be thinking about this? Did
someone mention it recently?
Season's greetings R.
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