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

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

Offset

1,1

Comments

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

A165330(a(n)) = 160;

Subsequence of A165336.

Links

Table of n, a(n) for n=1..52.

Example

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 ... .

Mathematica

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

Crossrefs

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

Sequence in context: A303958 A304601 A165338 * A305337 A322344 A316417

Adjacent sequences: A154874 A154875 A154876 * A154878 A154879 A154880

Keyword

nonn,base

Author

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

Extensions

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).

Status

approved