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 A079375 #23 Jan 21 2019 10:07:43
%S A079375 2,2,3,3,5,2,19,11,29,53,149,23,7,11,5,5,3,5,5,59,11,7,7,41,19,17,23,
%T A079375 7,5,3,7,3,11,3,3,5,2,5,3,3,53,11,5,3,41,13,29,97,13,11,2,11,5,7,7,17,
%U A079375 5,11,3,3,7,23,53,11,5,17,5,7,3,17
%N A079375 Costé prime expansion of Pi^2 - 9.
%C A079375 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 A079375 Nathaniel Johnston, <a href="/A079375/b079375.txt">Table of n, a(n) for n = 0..5000</a>
%H A079375 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 A079375 Digits := 200: 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 50 do p := P(y); t1 := [op(t1),p]; y := p*y-1; od; t1; end; F(Pi^2 - 9);
%t A079375 $MaxExtraPrecision = 500; P[x_] := Module[{y}, y = Ceiling[1/x]; If[PrimeQ[y], y, NextPrime[y]]]; F[x_] := Module[{y, i, t1}, y = x; t1 = {}; For[i = 1, i <= 100, i++, AppendTo[t1, p = P[y]]; y = p*y - 1]; t1]; F[Pi^2 -9] (* _G. C. Greubel_, Jan 20 2019 *)
%Y A079375 Cf. A079376, A079377, A079366, A079367, A079368.
%K A079375 nonn,easy
%O A079375 0,1
%A A079375 _N. J. A. Sloane_, Feb 16 2003