Permanents and determinants of (0,1) matrices

[Yuval Dekel]

In the reference, sequence A000409 is given and there Neil writes :

"What exactly is the difference between this sequence and A000410? -
   njas" .

Does someebody know ?

Yuval


>From: Ralf Stephan <ralf at ark.in-berlin.de>
>Reply-To: ralf at ark.in-berlin.de
>To: all at abouthugo.de
>CC: seqfan at ext.jussieu.fr
>Subject: Re: Permanents and determinants of (0,1) matrices
>Date: Sat, 1 Nov 2003 09:33:06 +0100
> > n=5
> > det       times
> >   0    21040112
>
>Member of
>%S A046747 1,10,338,42976,21040112,39882864736,292604283435872
>%N A046747 n X n rational {0,1}-matrices of determinant 0.
>%Y A046747 A046747(n) = 2^(n^2) - n! * binomial(2^n -1, n) + n! * 
>A000410(n). Cf. A000409, A002884.
>
>see also the refs therein.  Sorry if this has been mentioned already.
>
>
>ralf

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