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 A153230 #19 May 20 2025 03:18:56
%S A153230 1,3,22,596,43934,78778,249994
%N A153230 Numbers k such that the string k is found at position k^2 in the decimal digits of Pi.
%C A153230 a(5) > 10^4, if it exists. - _Amiram Eldar_, May 06 2024
%C A153230 From _Michael S. Branicky_, May 19 2025: (Start)
%C A153230 a(8) > 10^6.
%C A153230 Assuming uniformly random digits, the expected value is 0.9 terms per digit-length. (End)
%e A153230 22 is in the sequence because 22 occurs at position 484 (22^2) after the decimal point in the digits of Pi.
%t A153230 With[{m = 10^3}, s = Rest@ RealDigits[Pi, 10, m^2][[1]]; q[n_] := s[[n^2 + Range[0, IntegerLength[n] - 1]]] == RealDigits[n][[1]]; Select[Range[m - 1], q]] (* _Amiram Eldar_, May 06 2024 *)
%Y A153230 Cf. A000796, A057679, A057680, A109513, A109514.
%K A153230 nonn,base,more
%O A153230 1,2
%A A153230 _Gil Broussard_, Dec 21 2008
%E A153230 a(5)-a(7) from _Michael S. Branicky_, May 18 2025