|
%I M2829 #13 Jan 27 2014 08:57:35
%S 3,10,4,5,10,2,5,3,2,3,6,6,6,3,5,6,10,5,5,10,6,6,6,2,5,8,2,6,8,4,6,6,
%T 4,5,10,2,4,7,11,5,7,9,10,7,1,6,7,11,7,10,0,6,8,9,6,4,11,7,13,2,6,4,4,
%U 10,8,4,5,3,2,5,7,9,10,4,8,8,7,5,10,3
%N Number of iterations until 3n reaches 153 under x goes to sum of cubes of digits map.
%C a(n) = A165331(A008585(n)). [From _Reinhard Zumkeller_, Nov 21 2009]
%D J. Roberts, Lure of the Integers, Math. Assoc. America, 1992, p. 13.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%t Table[Length[NestWhileList[Total[IntegerDigits[#]^3]&,3n,#!=153&]]-1,{n,80}] (* _Harvey P. Dale_, Dec 19 2011 *)
%Y Cf. A055012. [From _Reinhard Zumkeller_, Nov 21 2009]
%K nonn,base
%O 1,1
%A _N. J. A. Sloane_, _Mira Bernstein_
|
