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A154877
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Numbers that eventually reach the cycle 160-217-352 under "x -> sum of cubes of digits of x" (see A055012).
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6
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16, 22, 61, 79, 97, 106, 115, 127, 151, 160, 172, 202, 217, 220, 229, 235, 238, 253, 271, 283, 292, 325, 328, 352, 382, 388, 445, 454, 457, 475, 511, 523, 532, 544, 547, 574, 601, 610, 709, 712, 721, 745, 754, 790, 823, 832, 838, 883, 907, 922, 970, 1006
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OFFSET
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1,1
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COMMENTS
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All the numbers are of the form 3n+1.
A165330(a(n)) = 160;
Subsequence of A165336.
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LINKS
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Table of n, a(n) for n=1..52.
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EXAMPLE
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Taking 79 as an example; 7^3+9^3=1072, 1^3+0^3+7^3+2^3=352, 3^3+5^3+2^3=160, 1^3+6^3+0^3=217, 2^3+1^3+7^3=352.
a(15)=229: 229 -> 2*2^3+9^3=745 -> 7^3+4^3+5^3+1=532 -> 5^3+3^3+2^3=160 -> 217 -> 352 -> 160 ... .
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MATHEMATICA
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okQ[n_]:=MemberQ[NestList[Total[IntegerDigits[#]^3]&, n, 20], 160]; Select[Range[1200], okQ] (* Harvey P. Dale, Jun 20 2011 *)
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CROSSREFS
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Cf. A154820, A154877, A165330, A165336, A165337, A165339.
Sequence in context: A303958 A304601 A165338 * A305337 A322344 A316417
Adjacent sequences: A154874 A154875 A154876 * A154878 A154879 A154880
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KEYWORD
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nonn,base
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AUTHOR
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Avik Roy (avik_3.1416(AT)yahoo.co.in), Jan 16 2009
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EXTENSIONS
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Further terms added by Avik Roy (avik_3.1416(AT)yahoo.co.in), Jan 20 2009
Corrected by Reinhard Zumkeller, Sep 17 2009.
Confirmed by Harvey P. Dale, Jun 20 2011
Entry revised by N. J. A. Sloane, Oct 13 2018 (merging older duplicate entry with this one).
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STATUS
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approved
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