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A165333
Numbers that eventually reach the fixed point 370 under "x -> sum of cubes of digits of x" (see A055012).
6
7, 19, 34, 37, 43, 58, 67, 70, 73, 76, 85, 88, 91, 109, 118, 124, 139, 142, 145, 148, 154, 157, 166, 169, 175, 178, 181, 184, 187, 190, 193, 196, 214, 223, 226, 232, 241, 247, 259, 262, 268, 274, 277, 286, 295, 304, 307, 319, 322, 334, 340, 343, 346, 355, 358
OFFSET
1,1
COMMENTS
A165330(a(n)) = 370;
Subsequence of A031179 and of A016777; a(n) mod 3 = 1.
EXAMPLE
a(3)=34: 34 -> 3^3+4^3=91 -> 9^3+1=730 -> 7^3+3^3+0=370.
MATHEMATICA
f[n_] := Plus@@(IntegerDigits[n]^3); Trajectory[n_] := Most[NestWhileList[f, n, UnsameQ , All]]; Select[Range[358], Last[Trajectory[#]] == 370&] (* Ant King, May 24 2013 *)
CROSSREFS
KEYWORD
base,nonn
AUTHOR
Reinhard Zumkeller, Sep 17 2009
STATUS
approved