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A218908
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Primes p such that k*p is greater than the greatest prime factor of p^k - 1 and p^k + 1 for k = 1 to k = 4.
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0
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OFFSET
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1,1
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LINKS
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EXAMPLE
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The greatest factors of 3373^4 - 1 , 3373^6 - 1 and 3373^8 - 1 are respectively: 317, 6379, 7369.
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PROG
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(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, ", ")))
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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