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A102326 Primes p such that the largest prime divisor of p^4+1 is less than p. 1
10181, 14051, 18979, 25253, 57173, 58013, 60101, 62497, 65951, 66541, 69457, 75931, 82241, 82261, 84229, 87721, 88339, 88819, 91499, 92333, 95917, 99523, 105557, 107747, 109229, 118493, 118927, 137339, 146291, 155399, 157019 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..31.

EXAMPLE

p = 10181, 1+p^4 = 10743894862923122 = 2*17*1657*4657*5113*8009, so the largest prime factor is 8009 < p = 10181.

MATHEMATICA

<<NumberTheory`NumberTheoryFunctions` Select[Prime[Range[15000]], Max[PrimeFactorList[1 + #^4]] < # &] (* Ray Chandler, Jan 08 2005 *)

Select[Prime[Range[15000]], FactorInteger[#^4+1][[-1, 1]]<#&] (* Harvey P. Dale, Feb 27 2017 *)

PROG

(PARI) isok(p) = isprime(p) && (vecmax(factor(p^4+1)[, 1]) < p); \\ Michel Marcus, Jul 09 2018

CROSSREFS

Cf. A000040, A065091, A073501.

Sequence in context: A184205 A128878 A050267 * A216262 A243410 A221119

Adjacent sequences:  A102323 A102324 A102325 * A102327 A102328 A102329

KEYWORD

nonn

AUTHOR

Labos Elemer, Jan 05 2005

EXTENSIONS

Extended by Ray Chandler, Jan 08 2005

STATUS

approved

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Last modified July 20 22:20 EDT 2019. Contains 325189 sequences. (Running on oeis4.)