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Start with X = n^2. Repeatedly replace X with X - ceiling(X/n); a(n) is the number of steps to reach 0.
9

%I #55 Sep 08 2022 08:46:18

%S 1,3,5,8,11,14,17,21,24,28,32,36,40,44,49,53,57,62,66,71,75,80,84,90,

%T 94,99,103,109,113,118,123,128,133,139,143,149,154,159,164,170,175,

%U 180,185,191,196,201,207,212,217,223,229,234,240,246,251,256,262,268,273,279,284,290,296,302,308

%N Start with X = n^2. Repeatedly replace X with X - ceiling(X/n); a(n) is the number of steps to reach 0.

%H Robert G. Wilson v, <a href="/A278586/b278586.txt">Table of n, a(n) for n = 1..1000</a>

%H Matthijs Coster, <a href="https://pyth.eu/uploads/user/ArchiefPDF/Pyth55-6.pdf">Een Eigen Rij - Uitslag Prijsvraag</a>, Pythagoras, Number 6, June 2016, pp. 20-21. The sequence was discovered by Pim Spelier.

%p A278586 := proc(n)

%p local x,a;

%p x := n^2 ;

%p a := 0 ;

%p while x <> 0 do

%p x:= x-ceil(x/n) ;

%p a := a+1 ;

%p end do:

%p a;

%p end proc: # _R. J. Mathar_, Dec 02 2016

%t f[n_] := Length@ NestWhileList[# - Ceiling[#/n] &, n^2, # > 1 &]; Array[f, 65] (* _Robert G. Wilson v_, Dec 01 2016 *)

%o (Magma) a:=[]; for n in [1..58] do k:=n^2; count:=0; while k gt 0 do count+:=1; k-:=Ceiling(k/n); end while; a[n]:=count; end for; a; // _Jon E. Schoenfield_, Dec 01 2016

%Y Cf. A052488.

%K nonn,easy

%O 1,2

%A _N. J. A. Sloane_, Dec 02 2016, based on discussions about the Pythagoras article in the Sequence Fans Mailing List, Dec 01 2016. _Jack Brennen_ provided the definition given here.