6 problems

Somos 4 conjecture. The Hankel transform of the expansion of $f(x)/x$ is a

Row sum polynomial conjecture. For every $n\geq 0$,

Robbins-number amalgamation conjecture. The principal minor sequence of this amalgamation is the sequence of Robbins numbers.

Let $M=(g(x),f(x))$ be a Riordan array, and let $P^{(n)}_M$ denote its $n$-th production matrix, defined by … Let $M^{(n)}$ be the matrix produced by $P^{(n)}_M$. Higher production…

General Somos 4 conjecture. The Hankel transform is an $(\alpha,\beta)$ Somos $4$ sequence, where

Let $P=(0,0)$ be a point on the elliptic curve … and let $\tilde a_n$ be defined by the continued-fraction generating function in the paper, using the coordinates $x_n=x(nP)$ and…