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Primes of the form m*2^phi(m)-1 with phi(m) the Euler function, in order of increasing m.
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%I #23 Feb 12 2014 18:17:43

%S 3,11,79,23,127,191,1114111,1151,5119,6143,654311423,172031,

%T 88774955854727217151,1618481116086271,107221699928436768767,

%U 7421703487487,120946279055359,145135534866431,47287796087390207

%N Primes of the form m*2^phi(m)-1 with phi(m) the Euler function, in order of increasing m.

%C Sorted along increasing n of the definition.

%H Vincenzo Librandi, <a href="/A046153/b046153.txt">Table of n, a(n) for n = 1..45</a>

%p with(numtheory); for n from 1 to 1000 do x := n*2^phi(n)-1: if isprime(x) then print(x): fi:od:

%t Select[Table[m*2^EulerPhi[m]-1, {m, 1, 170}], PrimeQ] (* _Jean-François Alcover_, Apr 04 2011 *)

%Y Cf. A046154.

%K nonn,nice

%O 1,1

%A _Felice Russo_

%E More terms from _Jud McCranie_, Jan 26 2000