OFFSET
1,1
EXAMPLE
3^2 - 1 = 2^3, 3^2 + 1 = 2*5 and 2*3 > 2 and 2*3 > 5
13^2 -1 = 2^3*3*7, 13^2 + 1 = 2*5*17 and 2*13 > 7 and 2*13 > 17
MATHEMATICA
Select[Prime[Range[PrimePi[1000]]], 2 # > FactorInteger[#^2 - 1][[-1, 1]] && 2 # > FactorInteger[#^2 + 1][[-1, 1]] &] (* T. D. Noe, Nov 07 2012 *)
PROG
(PARI) forprime(h=3, 2001, for(n=2, 2, a=h^n; b=a-1; c=a+1; d=vecmax(factor(b)[, 1]~); e=vecmax(factor(c)[, 1]~); g=h*n; if(g>d && g>e, print1(h, ", "))))
CROSSREFS
KEYWORD
nonn
AUTHOR
Robin Garcia, Nov 07 2012
STATUS
approved