This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A064118 #35 Feb 16 2025 08:32:45
%S A064118 1,3,7,85,1781,2780,112280,155025
%N A064118 Numbers k such that the first k digits of e form a prime.
%C A064118 The primes are given in A007512. Sequences A065815, A119344, A136583, A210706,... are analogs for gamma, sqrt(3), sqrt(10), 3^(1/3), .... The MathWorld page about "Constant Primes" lists further examples. - _M. F. Hasler_, Aug 31 2013
%D A064118 C. A. Pickover, The Mathematics of Oz, "2, 271, 2718281", Chapter 95, Camb.Univ.Press, UK 2002.
%H A064118 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/ConstantPrimes.html">Constant Primes</a>
%H A064118 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/eDigits.html">e Digits</a>
%H A064118 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/e-Prime.html">e-Prime</a>
%H A064118 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/IntegerSequencePrimes.html">Integer Sequence Primes</a>
%H A064118 <a href="/index/Con#constant_primes">Index entries related to "constant primes".</a>
%e A064118 a(2)=3 because the 3-digit number 271 is prime.
%t A064118 Do[If[PrimeQ[FromDigits[RealDigits[N[E, n + 10], 10, n][[1]]]], Print[n]], {n, 1, 2300}]
%Y A064118 Cf. A001113.
%Y A064118 Cf. A047658.
%K A064118 base,more,nonn
%O A064118 1,2
%A A064118 _Shyam Sunder Gupta_, Sep 09 2001
%E A064118 One more term from _Robert G. Wilson v_, Sep 28 2001
%E A064118 a(6) from _Eric W. Weisstein_, Jan 17 2005
%E A064118 a(7) from _Eric W. Weisstein_, Jul 03 2009
%E A064118 a(8) from _Eric W. Weisstein_, Oct 11 2010