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A038100 Numbers k such that k < first location of string of k in decimal expansion of Pi.

%I A038100 #17 Jul 10 2022 16:06:55
%S A038100 0,2,3,6,7,8,10,11,12,13,16,17,18,19,20,21,22,24,25,27,28,29,30,31,34,
%T A038100 36,37,39,40,42,44,45,47,48,49,52,54,55,56,57,60,61,63,66,67,68,70,72,
%U A038100 73,76,77,80,85,87,90,91,96,100,101,102,103,104,106,107,108
%N A038100 Numbers k such that k < first location of string of k in decimal expansion of Pi.
%C A038100 'Location' starts from the first digit after the decimal point and refers to the first digit of a(n).
%H A038100 Jinyuan Wang, <a href="/A038100/b038100.txt">Table of n, a(n) for n = 1..5000</a>
%H A038100 Dave Andersen, <a href="http://www.angio.net/pi/piquery">The Pi-Search Page</a>
%F A038100 a(n) < A014777(n). - _Michael S. Branicky_, Jul 10 2022
%o A038100 (Python)
%o A038100 from sympy import pi
%o A038100 from itertools import count, islice
%o A038100 digits_of_pi = str(pi.n(10**5))[1:-1]
%o A038100 def agen():
%o A038100     for k in count(0):
%o A038100         kloc = digits_of_pi.find(str(k))
%o A038100         assert kloc > 0, ("Increase precision", k)
%o A038100         if k < kloc: yield k
%o A038100 print(list(islice(agen(), 65))) # _Michael S. Branicky_, Jul 10 2022
%Y A038100 Cf. A000796, A014777, A038099.
%K A038100 nonn,base
%O A038100 1,2
%A A038100 _Patrick De Geest_, Feb 15 1999
%E A038100 Offset changed to 1 by _Jinyuan Wang_, Sep 04 2021