Some new series for $1/π$ motivated by congruences
Abstract: In this paper, we deduce a family of six new series for $1/\pi$; for example, $$\sum_{n=0}\infty\frac{41673840n+4777111}{5780n}W_n\left(\frac{1444}{1445}\right) =\frac{147758475}{\sqrt{95}\,\pi}$$ where $W_n(x)=\sum_{k=0}n\binom nk\binom{n+k}k\binom{2k}k\binom{2(n-k)}{n-k}xk$. To do so, we transform our series to series of the type $$\sum_{n=0}\infty\frac{an+b}{mn}\sum_{k=0}n\binom nk4$$ studied by Cooper in 2012. In addition, we pose $17$ new series for $1/\pi$ motivated by congruences; for example, we conjecture that $$\sum_{k=0}\infty\frac{4290k+367}{3136k}\binom{2k}kT_k(14,1)T_k(17,16)=\frac{5390}{\pi},$$ where $T_k(b,c)$ is the coefficient of $xk$ in the expansion of $(x2+bx+c)k$.
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