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Smallest cube containing exactly n 9's.
30

%I #13 Mar 20 2020 22:30:03

%S 0,729,29791,970299,994011992,997002999,499999005953,999700029999,

%T 999940001199992,999970000299999,991023990975990999,

%U 999997000002999999,299243659909999996099,999999700000029999999,929999949497863992829999,999100239990997599909999

%N Smallest cube containing exactly n 9's.

%C a(n)^(1/3) = A048374(n) is the index of the first occurrence of n in sequence A269249. - _M. F. Hasler_, Feb 21 2016

%H Giovanni Resta, <a href="/A036536/b036536.txt">Table of n, a(n) for n = 0..23</a>

%F a(n) = A048374(n)^3. - _M. F. Hasler_, Feb 21 2016

%t nsmall = Table[Infinity, 15];

%t For[i = 0, i <= 10^6, i++, n0 = Count[IntegerDigits[i^3], 9];

%t If[nsmall[[n0 + 1]] > i^3, nsmall[[n0 + 1]] = i^3]];

%t Cases[nsmall, _?NumberQ] (* _Robert Price_, Mar 20 2020 *)

%Y Cf. A048374, A036527 - A036535 for other digits 0 - 8.

%Y Analog for squares: A036516 = A048354^2.

%K nonn,base

%O 0,2

%A _David W. Wilson_

%E Extended with a(0) = 0 by _M. F. Hasler_, Feb 21 2016

%E a(12)-a(15) from _Giovanni Resta_, Jun 29 2018