General expanded form of $(x+y+z)^k$
77279
find the formula of trinomial expansion
35034
Multiplicative inverses for $Z_n$
33332
A classic exponential inequality: $x^y+y^x>1$
134619
Galois extension with $X^4-2aX^2+b\in\mathbb Q[X]$
133905
Intuitive proof of $\sum_{k=1}^{n} \binom{n}{k} k^{k-1} (n-k)^{n-k} = n^n$
28781
$k^{2}+(k+1)^{2}$ being a perfect square for infinitely many $k$
123159
Solutions of the diophantine equation $x+y+z=xyz$?
9223
Finding $\iiint_K (x^2 -z^2)\, dx\, dy \,dz$
110441
Closed form for a formula with a summation over $i\binom{n-i}{k-1}$, and combinatorial proof?
17508
Knowing $|z|$ and $|w|$ (and possibly $z\overline{w}$), what are $|z+w|^2$, $|zw|^2$, $|z-w|^2$, $|z/w|^2$?
129163
Showing that every positive integer can be represented in this form
45555
$(x+y)^c\le x^c+y^c$ for $0<c\le1$
19914
Closed form for $\sum_{n=0}^{\infty} \binom{n+k}{k} x^n$ (Negative Binomial Theorem)
52078
Multinomial Coefficients Definition in expansion of $(1+x+x^2+\cdots+x^l)^n$
153589
Integral basis of an extension of number fields
124135
A general formula for $\sum (k-1)(k-2)(k-3)$?
28109
Conjectural closed-form representations of sums, products or integrals