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%I #19 Sep 08 2022 08:46:11
%S 281,59221,769449701919846533025514621
%N Primes of the form 141^k - 140^k.
%C a(4) has 372 digits. - _Vincenzo Librandi_, Feb 22 2015
%C The values of k are 2, 3, 13, 173, ... - _Jinyuan Wang_, May 30 2020
%H Michael P. May, <a href="https://arxiv.org/abs/1510.01028">On the Existence and Frequency Distribution of the Shell Primes</a>, arXiv preprint arXiv:1510.01028 [math.CO], 2015.
%t Select[Table[141^n - 140^n, {n, 1000}], PrimeQ] (* _Vincenzo Librandi_, Feb 22 2015 *)
%o (Magma) [a: n in [0..600] | IsPrime(a) where a is 141^n-140^n]; // _Vincenzo Librandi_, Feb 22 2015
%o (PARI) select(m->ispseudoprime(m), vector(20, k, 141^k-140^k)) \\ _Jinyuan Wang_, May 30 2020
%Y Cf. A254298.
%K nonn
%O 1,1
%A _Michael P. May_, Feb 21 2015