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A099440 Primes of the form A000295(n)=2^n-n-1. 5

%I

%S 11,1013,16369,65519,67108837,1125899906842573,72057594037927879,

%T 1180591620717411303353,83076749736557242056487941267521419

%N Primes of the form A000295(n)=2^n-n-1.

%C The next term a(10)=2^2072-2073 has 624 decimal digits.

%C a(11) has 1882 decimal digits. - _Vincenzo Librandi_, Jul 18 2012

%H Vincenzo Librandi, <a href="/A099440/b099440.txt">Table of n, a(n) for n = 1..10</a>

%e a(2)=1013 because A000295(A099439(2))=2^10-10-1 is prime.

%t Select[Table[2^n-n-1,{n,0,7000}],PrimeQ] (* _Vincenzo Librandi_, Jul 18 2012 *)

%o (MAGMA) [ a: n in [1..200] | IsPrime(a) where a is 2^n-n-1 ]; // _Vincenzo Librandi_, Jul 18 2012

%Y Cf. A000295 2^n-n-1 (column 2 of the Eulerian numbers), A099439 2^n-n-1 is prime, A099441 2^n-n-1 is a semiprime, A099442 semiprimes in A000295.

%K nonn

%O 1,1

%A _Hugo Pfoertner_, Oct 18 2004

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Last modified October 23 17:37 EDT 2021. Contains 348215 sequences. (Running on oeis4.)