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A181664 Let f(m) = number of steps needed to reach a Harshad number when the map k->A062028(l) is iterated starting at m; a(n) = smallest m such that f(m) = n. 2

%I #22 Nov 29 2021 01:39:21

%S 15,19,14,28,23,16,22,65,55,142,134,130,119,109,95,79,71,58,47,37,32,

%T 25,17,13,11,44,256,245,235,815,1313,1489,1469,1510,1493,1480,1829,

%U 1828,1814,1789,1772,3115,4295,4276,4262,4246,4229,4216,4196,4177,4163,4147,4183,4166,4153,4142,4132,4118,4111,4094,4081,8914,8885,8857,8834,8809,8783,8761,8741,8722,8699,8674,8648,8626,8597,8569,8546,8530,8513,8491,8471,8452,8429,8413,8387,8365,8345,8326,8312,8287,8270,8248,8228,8209,8186,8170,8153,8140,31085,31072

%N Let f(m) = number of steps needed to reach a Harshad number when the map k->A062028(l) is iterated starting at m; a(n) = smallest m such that f(m) = n.

%C Terms were computed by _D. S. McNeil_, _Claudio Meller_ and _Hans Havermann_.

%D Eric Angelini, Posting to Sequence Fans Mailing List, Sep 20 2010

%H Eric Angelini, <a href="http://www.cetteadressecomportecinquantesignes.com/Harshad.htm">Chasing base-10 Harshad numbers</a>

%H E. Angelini, <a href="/A181664/a181664.pdf">Chasing base-10 Harshad numbers</a> [Cached copy, with permission]

%H Hans Havermann, <a href="http://chesswanks.com/seq/StepsToHarshad.txt">Steps to reach a Harshad</a>

%Y Cf. A062028, A005349, A181614.

%K nonn,base

%O 1,1

%A _N. J. A. Sloane_, Nov 18 2010

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Last modified March 28 12:26 EDT 2024. Contains 371254 sequences. (Running on oeis4.)