Theorems about the divisors of numbers contained in the form paa±qbb
A first page footnote by Rudio warns us that Euler says that most of these theorems are known to him only by "induction" their proofs appear in other places. This seems to be a forgotten article, with hardly any proofs, but it contains many conjectures that kept his attention for the next several years.
Original Source Citation
Commentarii academiae scientiarum Petropolitanae, Volume 14, pp. 151-181.
Opera Omnia Citation
Series 1, Volume 2, pp.194-222.