A227170 Numbers n such that (16^n + 15^n)/31 is prime.
3, 5, 13, 1439, 1669, 37691
Offset: 1
Programs
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PARI
is(n)=ispseudoprime((16^n+15^n)/31) \\ Charles R Greathouse IV, May 22 2017
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Jean-Louis Charton has authored 13 sequences. Here are the ten most recent ones:
is(n)=ispseudoprime((16^n+15^n)/31) \\ Charles R Greathouse IV, May 22 2017
is(n)=ispseudoprime((140^n+139^n)/279) \\ Charles R Greathouse IV, Jun 13 2017
is(n)=ispseudoprime((138^n+137^n)/275) \\ Charles R Greathouse IV, Jun 13 2017
is(n)=ispseudoprime((48^n+47^n)/95) \\ Charles R Greathouse IV, Jun 13 2017
is(n)=ispseudoprime((18^n+17^n)/35) \\ Charles R Greathouse IV, Jun 13 2017
a(1)=a(2)=a(3)=a(4)=1 since 2^2-1, 2^3-1, 2^5-1 and 2^7-1 are primes.
is(n)=ispseudoprime(44^n-43^n) \\ Charles R Greathouse IV, Jun 06 2017
Select[Prime[Range[PrimePi[1000]]], PrimeQ[101^# - 100^#] &] (* T. D. Noe, Aug 15 2012 *)
is(n)=ispseudoprime(101^n-100^n) \\ Charles R Greathouse IV, Jun 06 2017
Select[Prime[Range[PrimePi[1000]]], PrimeQ[87^# - 86^#] &] (* T. D. Noe, Aug 15 2012 *)
is(n)=ispseudoprime(87^n-86^n) \\ Charles R Greathouse IV, Jun 06 2017
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