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A145102 a(0) = a(1) = 1. a(n+1) = floor(n*a(n)/a(n-1)), for n >= 1.

%I A145102 #19 Feb 23 2025 11:22:15
%S A145102 1,1,1,2,6,12,10,5,3,4,12,30,27,10,4,5,18,57,53,16,5,6,25,91,83,21,6,
%T A145102 7,31,124,116,28,7,8,37,157,148,33,8,9,43,191,182,40,9,9,45,230,240,
%U A145102 50,10,10,51,265,275,56,11,11,57,300,310,62,12,12,63,336,346,67,12,12,69,402
%N A145102 a(0) = a(1) = 1. a(n+1) = floor(n*a(n)/a(n-1)), for n >= 1.
%C A145102 At n = 62 the sequence settles down and becomes quasi-periodic with a 6-loop. - _Ctibor O. Zizka_, Feb 21 2025
%H A145102 Michel Marcus, <a href="/A145102/b145102.txt">Table of n, a(n) for n = 0..10000</a>
%H A145102 <a href="/index/Rec#order_22">Index entries for linear recurrences with constant coefficients</a>, signature (2,-3,4,-5,6,-5,4,-3,2,-1,0,1,-2,3,-4,5,-6,5,-4,3,-2,1).
%F A145102 From _Ctibor O. Zizka_, Feb 21 2025: (Start)
%F A145102 For n >= 62,
%F A145102 a(n) = n/6 + floor((n - 2)*(n - 3)/12) - 1 if n mod 6 = 0,
%F A145102 a(n) = n if n mod 6 = 1,
%F A145102 a(n) = 12 if n mod 6 = 2 or 3,
%F A145102 a(n) = n - 1 if n mod 6 = 4,
%F A145102 a(n) = floor((n - 1)*(n - 2)/12) if n mod 6 = 5. (End)
%o A145102 (PARI) {print1(a=1, ",", b=1, ","); for(n=2, 71, print1(c=floor((n-1)*b/a), ","); a=b; b=c)} \\ _Klaus Brockhaus_, Oct 02 2008
%Y A145102 Cf. A145103.
%K A145102 nonn,easy
%O A145102 0,4
%A A145102 _Leroy Quet_, Oct 01 2008
%E A145102 More terms from _Klaus Brockhaus_ and _R. J. Mathar_, Oct 02 2008