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%I #15 Jun 18 2022 05:30:10
%S 1,4,75,9424,12669,331783
%N Numbers k such that the decimal expansion of Pi^k begins (after the decimal point) with k.
%C The terms of this sequence are related to those in A100322, but do not necessarily appear in that sequence since A100322(n) is defined as the smallest positive integer k such that the digits of the fractional part of Pi^k begin with n.
%e Pi^1 = 3.1...;
%e Pi^4 = 97.4...;
%e Pi^75 = 19330382693312372796273669213182810875.75...
%t p = N[Pi, 10^4]; f[n_] := Block[{r = RealDigits[p^n, 10, Max[5, n]]}, e = r[[2]]; FromDigits[ Take[r[[1]], {e + 1, e + 1 + Floor[ Log[10, n]]} ]]]; Do[ If[ f[n] == n, Print[n]], {n, 10^4}] (* _Robert G. Wilson v_, Nov 16 2004 *)
%Y Cf. A100322.
%K base,nonn,more
%O 1,2
%A Mark Hudson (mrmarkhudson(AT)hotmail.com), Nov 16 2004
%E a(6) from _Jon E. Schoenfield_, Mar 28 2015
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