%I #19 Feb 16 2025 08:33:20
%S 26,63,323,784
%N Numbers n such that first n digits of A091725 (decimal expansion of second exponential integral at 1, ExpIntegralEi[1]) gives a prime number.
%C a(5) > 10^4.
%H Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/ConstantPrimes.html">Constant Primes</a>
%H Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/IntegerSequencePrimes.html">Integer Sequence Primes</a>
%Y Cf. A091725.
%K nonn,more,base,changed
%O 1,1
%A _Robert Price_, Aug 23 2013