greedy computation of pseudoperfect numbers?
Maximilian Hasler
Maximilian.Hasler at martinique.univ-ag.fr
Tue Apr 8 20:13:55 CEST 2008
On 4/8/08, Maximilian Hasler <Maximilian.Hasler at martinique.univ-ag.fr> wrote:
> On 4/8/08, Richard Guy <rkg at cpsc.ucalgary.ca> wrote:
> > Can someone prove or find a counterexample
> > to the potential comment for A136446 --
> > ``odd members are A005231'' ?? R.
> smallest counter-example:
> 351351
searching this number gave (among others) the sequence
http://www.research.att.com/~njas/sequences/A065235
%S A065235 8925,32445,351351,442365,159427275,159587925,159677175
%N A065235 Odd numbers n such that a sum over a subset of divisors equal n.
After some thinking and browsing I understood: the definition should read,
%N A065235 Odd numbers n such that a sum over exactly one subset of
proper divisors equals n.
or
%N A065235 Odd numbers equal to the sum of one unique subset of their
proper divisors.
or
%N A065235 Odd numbers which can be written in exactly one way as sum
of a subset of their proper divisors.
M.H.
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