Karim Belabas on Sun, 24 Nov 2019 17:03:45 +0100


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Re: Finding the generating funcction for a theta sequence?


* Karim Belabas [2019-11-24 16:51]:
[...]
> So you can actually write it only in terms of F_2 (= mfeisenstein(2)). More
> precisely
> 
> (-12 B(2) + 152 B(4) + 36 B(6) - 2176 B(8) + 3640 B(12) - 1664 B(24)) . F_2
> 
> (where B(n) is the q -> q^n operator). In fact, from this description, your
> original form had level 12:
[...]

Sorry, this doesn't work out numerically. Which means (unless I goofed again),
that your F doesn't belong to the modular form space we assigned to it,
hence is not a modular form (i.e. it has poles).

Cheers,

    K.B.
--
Karim Belabas, IMB (UMR 5251)  Tel: (+33) (0)5 40 00 26 17
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