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 A065253 #12 Nov 15 2019 10:46:22
%S A065253 3,1,4,11,5,9,2,6,15,13,25,8,19,7,29,23,12,33,18,14,16,22,26,24,43,53,
%T A065253 28,63,32,17,39,35,0,42,38,48,34,21,49,27,31,36,59,73,69,79,83,37,45,
%U A065253 41,10,55,58,52,20,89,47,44,99,54,64,65,109,62,93,30,57,68,51,46,74,40
%N A065253 a(n) = 10*(A064823(n)-1) + A000796(n).
%C A065253 The sequence would be a permutation of the naturals if each of the digits 0,1,..,9 occur infinitely often in the decimal expansion of Pi. "Inverse": A065254
%H A065253 Reinhard Zumkeller, <a href="/A065253/b065253.txt">Table of n, a(n) for n = 1..10000</a>
%H A065253 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%H A065253 <a href="/index/Ph#Pi314">Index entries for sequences related to the number Pi</a>
%t A065253 terms = 100; Clear[cnt]; cnt[_] = n = 0;
%t A065253 Do[a[++n] = 10 (++cnt[k] - 1) + k, {k, RealDigits[Pi, 10, terms][[1]]}];
%t A065253 a /@ Range[terms] (* _Jean-François Alcover_, Nov 15 2019 *)
%o A065253 (Haskell)
%o A065253 a065253 n = a065253_list !! (n-1)
%o A065253 a065253_list = zipWith (+)
%o A065253 (map ((* 10) . (subtract 1)) a064823_list) a000796_list
%o A065253 -- _Reinhard Zumkeller_, Jul 14 2013
%Y A065253 Cf. A064823, A000796, A065254.
%K A065253 base,nice,nonn
%O A065253 1,1
%A A065253 Klaus Strassburger (strass(AT)ddfi.uni-duesseldorf.de), Oct 26 2001