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A072082
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Numbers divisible by the cube of the sum of their digits in base 10.
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2
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1, 10, 100, 200, 500, 512, 1000, 2000, 2401, 4913, 5000, 5103, 5120, 5832, 10000, 10206, 11000, 11200, 11664, 13122, 14000, 17576, 19000, 19683, 20000, 20412, 21141, 23000, 23328, 24010, 28000, 29160, 32000, 37000, 39366, 40000, 40824
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OFFSET
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1,2
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COMMENTS
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If k is a term, then 10 * k is a term. There are an infinite number of terms that are not divisible by 10. The numbers m = 24 * 10^(294 * k - 292) +1 are divisible by 7^3 = digsum(m)^3. Also, the numbers s = 491 * 10^(4624 * k - 4623) + 3, k >= 1, are divisible by 17^3 = digsum(s)^3. - Marius A. Burtea, Mar 18 2020
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LINKS
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EXAMPLE
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k=98415: sumdigits(98415)=27, q=98415=5*27*27*27.
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MATHEMATICA
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sud[x_] := Apply[Plus, IntegerDigits[x]] Do[s=sud[n]^3; If[IntegerQ[n/s], Print[n]], {n, 1, 10000}]
Select[Range[50000], Divisible[#, Total[IntegerDigits[#]]^3]&] (* Harvey P. Dale, Mar 22 2016 *)
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PROG
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(Magma) [k:k in [1..41000]| k mod &+Intseq(k)^3 eq 0]; // Marius A. Burtea, Mar 18 2020
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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STATUS
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approved
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