[seqfan] Re: A099172.

[Heinz, Alois]

The g.f. gives the terms of the sequence.

In Maple:

gf:=(1 + x*y + x^2*y^2)/(1 - x - y + x*y - x^2*y^2);
seq(seq(coeff(series(coeff(series(gf,y,m+1),y,m),x,d-m+1),x,d-m), 
m=0..d), d=0..9);

Best regards, Alois

Am 25.11.2013 02:13, schrieb L. Edson Jeffery:
> For the listed g.f.: (1 + xy + x^2y^2)/(1 - x - y + xy - x^2y^2) in
> A099172, expanding to series does not seem to generate the terms of the
> array. Maybe I am doing something wrong on my end, but could someone please
> check it and make any necessary corrections (and let me know)?
>
> Thanks,
>
> Ed Jeffery