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a(n)^3 is smallest cube containing exactly n 4's.
10

%I #18 Mar 23 2020 06:33:38

%S 4,14,114,164,763,3543,17066,13464,163974,757364,3421244,6727219,

%T 28902604,35685649,761777604,1350780517,2543012249,7633715304,

%U 101476238101,163186746514,353823251814,5708006133707

%N a(n)^3 is smallest cube containing exactly n 4's.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/CubicNumber.html">Cubic Number</a>

%t nsmall = Table[Infinity, 15];

%t For[i = 0, i <= 10^6, i++, n0 = Count[IntegerDigits[i^3], 4];

%t If[nsmall[[n0]] > i, nsmall[[n0]] = i]];

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

%Y Cf. A036531, A048365, A048366, A048367, A048368, A048370, A048371, A048372, A048373, A048374.

%K nonn,base,more

%O 1,1

%A _Patrick De Geest_, Mar 15 1999

%E a(15)-a(20) from _Lars Blomberg_, Jun 12 2011

%E a(21) from _Giovanni Resta_, Jun 29 2018

%E a(22) from _Giovanni Resta_, Mar 23 2020