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%I #11 May 06 2024 01:42:57
%S 1,3,22,596
%N Numbers k such that the string k is found at position k^2 in the decimal digits of Pi.
%C a(5) > 10^4, if it exists. - _Amiram Eldar_, May 06 2024
%e 22 is in the sequence because 22 occurs at position 484 (22^2) after the decimal point in the digits of Pi.
%t 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 Cf. A000796, A057679, A057680, A109513, A109514.
%K base,more,nonn
%O 1,2
%A _Gil Broussard_, Dec 21 2008