30 May
2018
30 May
'18
6:53 p.m.
https://www.ams.org/journals/proc/1957-008-02/S0002-9939-1957-0085275-8/S000... A positive integer is the sum of three squares unless it is of the form 4^a (8n+7). -- Gene On Wednesday, May 30, 2018, 5:40:02 PM PDT, Allan Wechsler <acwacw@gmail.com> wrote: I remembered that somebody had asked, but I couldn't remember in what forum. I should have searched. And I don't think anybody mentioned, at the time, that the corresponding problem for 2 cubes was completely solved. (I believe that sums of 3 squares have been characterized completely, am I right?)