New posts in Quadratic Forms

If $p$ is prime, then $x^2 +5y^2 = p \iff p\equiv 1,9 $ mod $(20)$.

Is the $\mathbb{Z}$-grading of a Clifford algebra basis independent?

Solving a non-zero quadratic equation of two variables

Diagonalizability of symmetric bilinear forms over fields of characteristic $2$

The set of primes of the form $a^2+8b^2$, where $a,b\in\mathbb N_+$

Equivalence of two multisets of natural numbers

Write $(x^2 + y^2 + z^2)^2 - 3 ( x^3 y + y^3 z + z^3 x)$ as a sum of (three) squares of quadratic forms

$\mathbb{Z}[\sqrt{11}]$ is norm-euclidean

Set of quadratic expressions $nx^2+m$ whose union is all integers?

Are there prime numbers not irreducible in $\mathcal{O}_{\mathbb{Q}(\sqrt{577})}$?