E718  Facillima methodus plurimos numeros primos praemagnos inveniendi
(An easy method of finding several rather large prime numbers)
Summary:
Euler uses one of his idoneal numbers, 232, to look for big prime numbers. It seems that if a number is of the
two forms naa + 1 and nxx + yy and n is idoneal, then it is prime. Euler finds 124 values of a, up to 299,
that give prime numbers in this form: 232*299^{2} + 1 = 20741033 is prime and is over 20 million.
Publication:

Originally published in Nova Acta Academiae Scientarum Imperialis Petropolitinae 14, 1805, pp. 310

Opera Omnia: Series 1, Volume 4, pp. 352  359
 Reprinted in Commentat. arithm. 2, 1849, pp. 215219 [E718a]
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