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 A080351 #15 Jun 11 2025 13:18:27
%S A080351 3,11,11,2,13,23,17,23,7,7,5,3,13,11,5,3,23,17,7,5,5,3,5,3,5,5,3,5,2,
%T A080351 149,19,103,577,389,1039,223,29,11,3,3,7,5,2,7,3,191,47,13,11,7,5,3,7,
%U A080351 3,7,13,29,11,3,3,3,3,5,5,2,5,2,5,3,79,137,173,59,157,29,17,7,13,79,281
%N A080351 Costé prime expansion of 1/exp(1).
%C A080351 For x in (0,1], define P(x) = min{p: p prime, 1/x < p}, Phi(x) = P(x)x - 1. Costé prime expansion of x(0) is sequence a(0), a(1), ... given by x(n) = Phi(x(n-1)) (n>0), a(n) = P(x(n)) (n >= 0).
%H A080351 A. Costé, <a href="http://www.emis.de/journals/EM/expmath/volumes/11/11.3/Coste383_405.pdf">Sur un système fibré lié à la suite des nombres premiers</a>, Exper. Math., 11 (2002), 383-405.
%p A080351 Digits := 500: P := proc(x) local y; y := ceil(evalf(1/x)); if isprime(y) then y else nextprime(y); fi; end; F := proc(x) local y,i,t1; y := x; t1 := []; for i from 1 to 100 do p := P(y); t1 := [op(t1),p]; y := p*y-1; od; t1; end; F(1/exp(1));
%Y A080351 Cf. A001113, A079385, A079386, A079366, A079367, A079368, A080348, A080349, A080350.
%K A080351 nonn,easy
%O A080351 0,1
%A A080351 Mark Hudson (mrmarkhudson(AT)hotmail.com), Feb 17 2003