acb_dirichlet_zeta_jet

Sets res (a vector of length len) to the Taylor coefficients of $\zeta(s + x)$, or of the deflated function $\zeta(s + x) - 1/(s + x - 1)$ if deflate is nonzero. Euler–Maclaurin summation is used (after the reflection formula when $\operatorname{Re}(s) \le -4$, or $\le -2.5$ at precision below 128 bits; for larger negative $\operatorname{Re}(s)$ it is cheaper and loses fewer bits to sum directly at $s$, with guard bits proportional to $-\operatorname{Re}(s) \log_2 p$), the Riemann–Siegel formula for len $\le 2$ high on the critical line, or, for an exact rational number $s$ of small height (including integers) at very high precision, the approximate functional equation (acb_dirichlet_l_fmpq_afe_jet), whose cost is $\tilde O(p^{1.5})$ instead of $\tilde O(p^2)$ and which needs far less memory.