Search: a061341 -id:a061341
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A009421
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Cubes, not ending in 0, formed by concatenating other cubes.
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+10
2
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10648, 27818127, 1018108216, 11728027648, 27081081027, 216108018001, 216648648216, 1001801080216, 27008100810027, 125112533753375, 125180086413824, 216010800180001, 216064806480216, 216270112515625, 1000180010800216, 1728648081003375, 1812501158328125
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OFFSET
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1,1
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LINKS
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FORMULA
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EXAMPLE
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2272^3 = 1_1728_0_27_64_8.
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PROG
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(Python)
from sympy import integer_nthroot
def iscube(n): return integer_nthroot(n, 3)[1]
def ok3(n, c):
if n%10 == 9 or (c == 1 and n%10 == 0): return False
if c > 1 and iscube(n): return True
d = str(n)
for i in range(1, len(d)):
if iscube(int(d[:i])) and ok3(int(d[i:]), c+1): return True
return False
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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R. Muller
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EXTENSIONS
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STATUS
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approved
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