|
%I #15 Mar 29 2019 20:00:48
%S 1,2,145,180,691,4123
%N Numbers n such that first n digits of A091723 (Decimal expansion of the root x of ExpIntegralEi[x]==0) gives a prime number.
%C a(7) > 10^4.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/ConstantPrimes.html">Constant Primes</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/IntegerSequencePrimes.html">Integer Sequence Primes</a>
%Y Cf. A091723.
%K nonn,more,less,base
%O 1,2
%A _Robert Price_, Aug 23 2013
|
