cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A062648 Numbers k such that 82^k - 81^k is prime.

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%I A062648 #19 Jul 04 2021 09:01:48
%S A062648 2,3,13,787,797,857,1613,37337
%N A062648 Numbers k such that 82^k - 81^k is prime.
%C A062648 Terms greater than 1000 are often only strong pseudoprimes.
%C A062648 a(9) > 10^5. - _Robert Price_, Jan 28 2015
%t A062648 Select[Range[1000], PrimeQ[82^# - 81^#] &] (* _Robert Price_, Jan 28 2015 *)
%o A062648 (PARI) is(n)=ispseudoprime(82^n-81^n) \\ _Charles R Greathouse IV_, Jun 13 2017
%Y A062648 Cf. A000043, A057468, A059801, A059802, A062572-A062666.
%K A062648 nonn,hard
%O A062648 1,1
%A A062648 _Mike Oakes_, May 18 2001, May 19 2001
%E A062648 a(8) from _Robert Price_, Jan 28 2015