On very large prime numbers
In this article, Euler is interested in finding large prime numbers. He also reproves that the fifth Fermat number 225+1 is not prime. Euler provides factor tables for aa+1, for a<1500. It is followed by a German-language article by Johann Albrecht Euler.
Original Source Citation
Novi Commentarii academiae scientiarum Petropolitanae, Volume 9, pp. 99-153.
Opera Omnia Citation
Series 1, Volume 3, pp.1-45.