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A352721
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Perfect cubes whose decimal digits appear in nonincreasing order.
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0
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0, 1, 8, 64, 1000, 8000, 64000, 1000000, 8000000, 64000000, 1000000000, 8000000000, 64000000000, 1000000000000, 8000000000000, 64000000000000, 1000000000000000, 8000000000000000, 64000000000000000, 1000000000000000000, 8000000000000000000, 64000000000000000000
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OFFSET
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1,3
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LINKS
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FORMULA
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EXAMPLE
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64 is in the sequence because it is a perfect cube (64 = 4^3) whose digits appear in nonincreasing order.
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MATHEMATICA
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Select[Range[0, 4*10^6]^3, Max@ Differences[IntegerDigits[#]] <= 0 &] (* Amiram Eldar, Mar 30 2022 *)
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PROG
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(PARI) ok(n) = digits(n) == vecsort(digits(n), , 4) && ispower(n, 3)
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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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STATUS
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approved
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