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%I #11 Sep 08 2022 08:45:19
%S 2,3,4,5,7,11,15,26,52,116,359,1547,2465
%N Numbers n such that (n+1)*n^n-1 is prime.
%e 15 is in the sequence because (15+1)*15^15-1 = 16*15^15-1 = 7006302246093749999, which is prime.
%t Select[Range[1000], PrimeQ[(# + 1) #^# - 1] &] (* _Vincenzo Librandi_, Oct 23 2014 *)
%o (PARI) isok(n) = isprime((n+1)*n^n-1); \\ _Michel Marcus_, Oct 23 2014
%o (Magma) [n: n in [1..1000] |IsPrime((n+1)*n^n-1)]; // _Vincenzo Librandi_, Oct 23 2014
%Y Cf. A108879.
%K more,nonn
%O 1,1
%A _Ray G. Opao_, Jun 30 2005
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