A185397 Largest number x such that the greatest prime factor of x^2+2 is A033203(n), the n-th prime not congruent to 5 or 7 mod 8.

22, 140, 707, 21362, 4991, 1306066, 137965, 2294636, 31768298, 1557652, 340064590, 38439662, 105080665, 273502688, 543164542, 9575480365630, 391890109484, 14629598023, 80849485336, 1241646894380

Offset

1,1

Comments

For any prime p, there are finitely many x such that x^2+2 has p as its largest prime factor.

Links

Table of n, a(n) for n=1..20.

Filip Najman, Smooth values of some quadratic polynomials, Glasnik Matematicki Series III 45 (2010), pp. 347-355.

Filip Najman, Home Page (gives all 914 numbers x such that x^2+2 has no prime factor greater than 193)

Crossrefs

Equivalents for other polynomials: A175607 (x^2 - 1), A145606 (x^2 + x), A185389 (x^2 + 1), A185396 (x^2 - 2).

Sequence in context: A263481 A238170 A275799 * A179792 A125332 A126490

Adjacent sequences: A185394 A185395 A185396 * A185398 A185399 A185400

Keyword

nonn

Author

Charles R Greathouse IV, Feb 21 2011

Status

approved