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%I #13 Dec 13 2016 20:34:56
%S 0,0,0,0,0,0,0,0,0,1,0,0,0,1,0,0,1,1,0,1,0,1,0,0,0,0,0,1,1,1,0,2,0,1,
%T 1,0,0,0,0,2,0,1,0,1,0,1,1,0,1,1,0,0,0,0,0,0,0,1,1,1,0,1,0,0,0,0,1,0,
%U 0,1,0,1,0,1,0,0,1,0,0,2,0,0,0,0,1,0,0,0,0,2,1,0,0,0,0,0,0,1,2,3,0
%N Number of times the digit 9 appears in the decimal expansion of n^3.
%C The cubes corresponding to the first occurrence of 1, 2, 3, ... are listed in A036535, i.e., A036535(n)^(1/3) = A048374(n) is the index of the first occurrence of n.
%H G. C. Greubel, <a href="/A269249/b269249.txt">Table of n, a(n) for n = 0..1000</a>
%e 0^3 = 0, 1^3 = 1, 2^3 = 8, 3^3 = 27, 4^3 = 64, ... and 8^3 = 512 all have a(0) = a(1) = ... = a(8) = 0 digits '9'.
%e 9^3 = 729 has a(9) = 1 digit '9'.
%t DigitCount[(Range[0, 100])^3, 10, 9] (* _G. C. Greubel_, Dec 13 2016 *)
%o (PARI) A269249(n)=#select(t->t==9,digits(n^3))
%Y Cf. A036536 and A036527 - A036535; A048374 and A048365 - A048373.
%Y Analog for the other digits 0, 1, ..., 8: A269250, A269241, A269242, A269243, A269244, A269245, A269246, A269247, A269248.
%Y Analog for squares: A086017 (digit 9) and A086008 - A086016 for digits 0 - 8.
%K nonn,base
%O 0,32
%A _M. F. Hasler_, Feb 20 2016
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