[seqfan] Re: Numbers such that there exist a(n) consecutive triangle numbers which sum to a square.

[Andrew Weimholt]

On Sun, Apr 18, 2010 at 7:02 AM, Max Alekseyev <maxale at gmail.com> wrote:
> Alternatively this sequence can be defined as the values of d for which
>
> binomial(x+d,3) - binomial(x,3) = square
>
> has nonnegative solutions with respect to x.
>

Yes - differences of tetrahedral numbers. In fact, that is how
I arrived at the diophantine equation.

Andrew