Consider a Dirichlet character, $\chi(n)$, and the partial sum :

$$S(\chi,x)=\bigg |\sum_{n=1}^{x} \chi(n)\bigg|$$

There are many works to bound this sum when $\chi$ is a primitive character, but what can we say if $\chi$ is not primitive ?

More specifically if we fix a primitive Dirichlet character $\chi$ and then define from it a suite of non primitive character $\chi_N$ defined by:

$$\forall n, \chi_1(n)=\chi(n)$$

$$\forall n, \chi_N(n)=\chi_{N-1}(n).\chi^{P_N} (n)$$

Where $\chi^{P_N} (n)$ is the principal Dirichlet character associated to the N-th prime number (not considering 2).

(so $\chi^{P_N} (n)$ is the principal character simply defined by : $\chi^{P_N} (n) =0 $ if n is a multiple of the N-th prime number $P_N$ and 1 if not)

This suite of character is build from original character by "removing at each step a prime".

Question : how will evolute the max of $S(\chi^{P_N},x)$ for these charcaters ?

I would like to show that in this suite there are an infinity of characters with their $Max(S(\chi^{P_N},x))$ lower than a fix constant ? Is it realistic ?

Any reference on bounding partial sum of imprimitive characters ?

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