Search: id:A117706 Results 1-1 of 1 results found. %I A117706 %S A117706 1,7,13,35,53,115,145,307,10163 %N A117706 Numbers n such that 6^n-n^6 is prime. %C A117706 a(9) found by Donovan Johnson %C A117706 Comment by Donovan Johnson : A117705 and A117706 are both Fermat probable prime to four bases. They have also passed a Miller-Rabin primality test in five randomly chosen bases. I checked the n values up to 70000 for A117705 and n values up to 60000 for A117706. No additional primes or probable primes were found. %e A117706 a(2)=7 because 6^7 - 7^6 = 162287 is prime %t A117706 Do[If[PrimeQ[(6^n-n^6)],Print[n]],{n,1,3000}] %Y A117706 Sequence in context: A060983 A001001 A067692 this_sequence A066673 A155036 A088985 %Y A117706 Adjacent sequences: A117703 A117704 A117705 this_sequence A117707 A117708 A117709 %K A117706 hard,more,nonn %O A117706 1,2 %A A117706 Mohammed Bouayoun (Mohammed.Bouayoun(AT)sanef.com), Apr 13 2006, Jan 08 2008 Search completed in 0.001 seconds