### Oblong Numbers Representable as Sums of Two Squares and Primes of the Form $4u^2+1$

1) Click here for Mathematica notebook which generates solutions to: $u^2 + t^2 = n(n+1)$

2) Click here for: "A Model for the Sum of Two Squares" pdf (an interesting visualization tool)
*Researchers with Autocad can click here for a lisp routine to explore the sums of squares model.
*Click here for an wmv file  (9 meg) which shows the lisp routine working.

3) Excel file with prime values of $u \in S$ up to 1000, indicating whether t is also prime.
4) What went wrong in section two of arxiv.org submission? (pdf)

The density of lattice points that satisfy $u^2+t^2=n(n+1)$ enclosed in a circle of indicated radius.