%I #8 Oct 31 2013 12:17:24
%S 2,71,271,4523,74713,904523,2718281,72407663,360287471,7427466391,
%T 75724709369,749669676277,8284590452353,99959574966967,
%U 724709369995957,2470936999595749,28459045235360287,571382178525166427
%N First prime of length n encountered in the decimal representation of e.
%t f[n_] := Select[FromDigits /@ Partition[ First[ RealDigits[E, 10, 1000]], n, 1], PrimeQ, 1][[1]]; Array[f, 20] (* _Robert G. Wilson v_, Nov 14 2011 *)
%Y Cf. A007512.
%K base,nonn
%O 1,1
%A Mark Cooke (rm_cooke(AT)yahoo.com), Jul 12 2004