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A154877 Numbers that eventually reach the cycle 160-217-352 under "x -> sum of cubes of digits of x" (see A055012). 6

%I

%S 16,22,61,79,97,106,115,127,151,160,172,202,217,220,229,235,238,253,

%T 271,283,292,325,328,352,382,388,445,454,457,475,511,523,532,544,547,

%U 574,601,610,709,712,721,745,754,790,823,832,838,883,907,922,970,1006

%N Numbers that eventually reach the cycle 160-217-352 under "x -> sum of cubes of digits of x" (see A055012).

%C All the numbers are of the form 3n+1.

%C A165330(a(n)) = 160;

%C Subsequence of A165336.

%e 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.

%e 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 ... .

%t okQ[n_]:=MemberQ[NestList[Total[IntegerDigits[#]^3]&,n,20],160]; Select[Range[1200],okQ] (* _Harvey P. Dale_, Jun 20 2011 *)

%Y Cf. A154820, A154877, A165330, A165336, A165337, A165339.

%K nonn,base

%O 1,1

%A Avik Roy (avik_3.1416(AT)yahoo.co.in), Jan 16 2009

%E Further terms added by Avik Roy (avik_3.1416(AT)yahoo.co.in), Jan 20 2009

%E Corrected by _Reinhard Zumkeller_, Sep 17 2009.

%E Confirmed by _Harvey P. Dale_, Jun 20 2011

%E Entry revised by _N. J. A. Sloane_, Oct 13 2018 (merging older duplicate entry with this one).

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Last modified May 19 04:06 EDT 2019. Contains 323377 sequences. (Running on oeis4.)