OFFSET
1,1
EXAMPLE
The greatest factors of 3373^4 - 1 , 3373^6 - 1 and 3373^8 - 1 are respectively: 317, 6379, 7369.
PROG
(PARI) forprime(h=3, 400000, f=h^3-1; g=h^3+1; k=vecmax(factor(f)[, 1]~); l=vecmax(factor(g)[, 1]~); m=h^4-1; n=h^4+1; o=vecmax(factor(m)[, 1]~); p=vecmax(factor(n)[, 1]~); if(3*h>k && 3*h>l && 4*h>o && 4*h>p, print1(h, ", ")))
CROSSREFS
KEYWORD
nonn
AUTHOR
Robin Garcia, Nov 08 2012
STATUS
approved