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A143504 Numbers k such that k > first location of string of k in decimal expansion of e.

%I A143504 #6 Jul 10 2022 16:07:14
%S A143504 7,8,18,23,28,35,36,45,47,49,52,53,57,59,60,62,66,67,69,70,71,72,74,
%T A143504 75,76,77,81,82,84,87,90,93,94,95,96,97,99,135,138,166,174,178,181,
%U A143504 182,193,195,200,217,218,232,233,235,240,244,247,249,251,260,264,266
%N A143504 Numbers k such that k > first location of string of k in decimal expansion of e.
%C A143504 'Location' starts from the first digit after the decimal point and refers to the first digit of a(n).
%H A143504 Michael S. Branicky, <a href="/A143504/b143504.txt">Table of n, a(n) for n = 1..10000</a>
%H A143504 Robert Nemiroff and Jerry Bonnell, <a href="http://antwrp.gsfc.nasa.gov/htmltest/gifcity/e.1mil">The Number e to 1 Million Digits</a>.
%F A143504 a(n) > A078197(n). - _Michael S. Branicky_, Jul 10 2022
%e A143504 1 is not a term since it is less than its location in e, 2.
%e A143504 7 is a term since it is greater than its location in e, 1.
%e A143504 18 is a term since it is greater than its location in e, 2.
%o A143504 (Python)
%o A143504 from sympy import E
%o A143504 from itertools import count, islice
%o A143504 digits_of_e = str(E.n(10**5))[1:-1] # raise to 10**6 for b-file
%o A143504 def agen():
%o A143504     for k in count(1):
%o A143504         kloc = digits_of_e.find(str(k))
%o A143504         assert kloc > 0, ("Increase precision", k)
%o A143504         if k > kloc: yield k
%o A143504 print(list(islice(agen(), 60))) # _Michael S. Branicky_, Jul 10 2022
%Y A143504 Cf. A001113, A038099, A078197.
%K A143504 base,nonn
%O A143504 1,1
%A A143504 Leonid Ianoushevitch (leonid163(AT)mail.ru), Oct 24 2008
%E A143504 Terms corrected and a(45) and beyond from _Michael S. Branicky_, Jul 10 2022