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A052072
Smallest cubes whose digits occur with the same frequency n.
5
0, 1331, 700227072, 22676697737363992239, 1728999927211172788179288, 256263633328535368685258882625, 19194114355415391344355399945943513
OFFSET
1,2
EXAMPLE
22676697737363992239 (= 2830479^3) and its digits 2, 3, 6, 7 and 9 each occur four times.
MATHEMATICA
Table[i = 0;
While[x = i^3; Union@DeleteCases[DigitCount[x], 0] != {n}, i++];
x, {n, 7}] (* Robert Price, Oct 12 2019 *)
Select[Range[400]^3, Length[Union[DeleteCases[DigitCount[#], 0]]]==1&] (* Harvey P. Dale, Apr 30 2022 *)
PROG
(Python)
def A052072(n):
a, b, c = 0, 0, 0
for i in range(10**9):
s = str(c)
for d in set(s):
if s.count(d) != n:
break
else:
return c
c += a + b + 1
b += 2*a + 3
a += 3
return 'search limit reached.' # Chai Wah Wu, Aug 11 2015
CROSSREFS
KEYWORD
nonn,base,more,nice
AUTHOR
Patrick De Geest, Jan 15 2000
EXTENSIONS
Offset corrected by Michel Marcus, Aug 12 2015
a(7) from Giovanni Resta, Aug 19 2018
STATUS
approved