[seqfan] a puzzle sequence A100696
Max Alekseyev
maxale at gmail.com
Thu Apr 19 19:58:25 CEST 2012
SeqFans,
I've tracked down the actual source of A100696.
It was posed as a puzzle by Prof. E. A. Roganov from Moscow State
Industrial University at one his seminars.
Its was never solved, while the solution is the following:
A100696 contains such weird numbers m that the sum of its divisors
smaller than A033880(m) is greater than A033880(m).
It may be easily noticed that for an abundant number m, if the sum of
its divisors smaller than A033880(m) is smaller than A033880(m), then
m is necessarily weird.
So A100696 lists those weird numbers that cannot be detected this way.
I would appreciate if somebody edit and extend A100696 based on this
information.
Thanks,
Max
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