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%I #19 Apr 14 2020 15:40:38
%S 1,10,100,112,121,211,778,787,877,1000,1012,1021,1102,1120,1189,1198,
%T 1201,1210,1234,1243,1324,1342,1423,1432,1579,1597,1759,1795,1819,
%U 1891,1918,1957,1975,1981,2011,2101,2110,2134,2143,2314,2341,2413,2431,2779
%N Numbers that eventually reach 1 under "x -> sum of cubes of digits of x".
%C Subsequence of A016777; a(n) mod 3 = 1; A165330(a(n))=1. [_Reinhard Zumkeller_, Sep 17 2009]
%D R. K. Guy, Unsolved Problems Number Theory, Sect. E34.
%H R. Zumkeller, <a href="/A035504/b035504.txt">Table of n, a(n) for n = 1..1000</a>
%H R. Styer, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL13/Styer/styer5.html">Smallest Examples of Strings of Consecutive Happy Numbers</a>, J. Int. Seq. 13 (2010), 10.6.3, Section 4.
%t f[n_]:=Plus@@(IntegerDigits[n]^3);Trajectory[n_] := Most[NestWhileList[f, n, UnsameQ, All]];Select[Range[2780],Last[Trajectory[#]]==1 &] (* _Ant King_, May 24 2013 *)
%Y Cf. A007770.
%Y Cf. A046197, A008585, A165333, A165334, A165335; subsequence of A031179.
%K nonn,easy,base
%O 1,2
%A _N. J. A. Sloane_.
%E More terms from Larry Reeves (larryr(AT)acm.org), Mar 31 2000
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