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Primes of the form m^k-k, with m and k > 1.
4

%I #10 Jun 06 2021 09:01:21

%S 2,5,7,23,47,61,79,167,223,359,439,503,509,727,839,997,1019,1087,1223,

%T 1367,1847,2207,2399,2741,3023,3719,3967,4093,4759,5039,5623,5927,

%U 6553,7919,8179,8647,10607,11447,13687,14159,14639,15619,16127,17159,17573

%N Primes of the form m^k-k, with m and k > 1.

%C It appears that primes of this form are much more common than primes of the form m^k+k (A099227).

%H Vincenzo Librandi, <a href="/A099228/b099228.txt">Table of n, a(n) for n = 1..1000</a>

%t nLim=32000; lst={}; Do[k=2; While[n=m^k-k; n<=nLim, AppendTo[lst, n]; k++ ], {m, 2, Sqrt[nLim]}]; Select[Union[lst], PrimeQ]

%Y Cf. A057897 (numbers of the form m^k-k, with m and k > 1), A084746 (least k such that n^k-k is prime).

%Y Cf. A099227.

%K nonn

%O 1,1

%A _T. D. Noe_, Oct 06 2004