It is known that the sum $\Phi_k(M)=\displaystyle\sum_{n=0}^M(-1)^nn^k$ can be written by Euler polynomials and $F_k(N)$ can be written by Bernoulli polynomials. Historically , Euler on page 499 of "L.Euler, Institutiones Calculi Differentialis, Petersberg,1755" ([Euler archive link](https://math.dartmouth.edu/~euler/pages/E212.html)), introduced Euler polynomials, to evaluate the alternating sum $\Phi_k(M)$ More precisely, $$\sum_{i=0}^{n-1}i^p=\frac{1}{p+1}\sum_{k=0}^p\binom{p+1}{k}B_kn^{p+1-k}$$ where $B_k$ are Bernoulli numbers and can be defined by following generating function $$\frac{x}{e^x-1}=\sum_{k=0}^\infty B_k\frac{x^k}{k!}$$ See this paper for irreducibility for such polynomials Duke Math. J. Volume 19, Number 3 (1952), 475-481. Note on irreducibility of the Bernoulli and Euler polynomials L. Carlitz http://projecteuclid.org/euclid.dmj/1077477373