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%I #32 Aug 19 2024 02:21:06
%S 1,2,4,6,30,32,42,120,210,248,284,574,600,628,1600,2800,3396,8892,
%T 9426,14630,15444,37384,51062,76364,129566
%N Numbers k such that k*2^k - (k-1) is prime.
%C All terms > 1 are even. - _Robert Israel_, Sep 22 2014
%p select(t -> isprime(t*2^t - (t-1)), [$1..5000]); # _Robert Israel_, Sep 22 2014
%o (PARI) is(n)=ispseudoprime(n*2^n-(n-1)) \\ _Charles R Greathouse IV_, May 22 2017
%Y Cf. A046846.
%K nonn,hard,more
%O 1,2
%A _Felice Russo_
%E New name from _Michel Marcus_, Sep 22 2014
%E a(12)-a(17) from _Robert Israel_, Sep 22 2014
%E a(18)-a(23) from _Michael S. Branicky_, May 12 2023
%E a(24)-a(25) from _Michael S. Branicky_, Aug 18 2024