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A048368
a(n)^3 is smallest cube containing exactly n 3's.
10
17, 7, 179, 477, 707, 6935, 15477, 44197, 535677, 693368, 2028209, 7566137, 32215777, 62446477, 322024127, 2027400657, 5171307877, 15373346477, 28575396477, 237304541491, 322033146477, 5105022776547, 4536383124177
OFFSET
1,1
LINKS
Eric Weisstein's World of Mathematics, Cubic Number
EXAMPLE
477^3 = 108531333 is the first cube containing four 3's, so a(4) = 477.
MATHEMATICA
nsmall = Table[Infinity, 15];
For[i = 0, i <= 10^6, i++, n0 = Count[IntegerDigits[i^3], 3];
If[nsmall[[n0]] > i, nsmall[[n0]] = i]];
Cases[nsmall, _?NumberQ] (* Robert Price, Mar 20 2020 *)
KEYWORD
nonn,base,more
AUTHOR
Patrick De Geest, Mar 15 1999
EXTENSIONS
a(14)-a(16) from Simon Nickerson (simonn(AT)maths.bham.ac.uk), Aug 12 2005
a(17)-a(20) from Lars Blomberg, Jun 12 2011
a(21)-a(23) from Giovanni Resta, Jun 29 2018
STATUS
approved