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A175019 a(0)=a(1)=1; a(n) = a(n-a(n-2)) + 2.

%I A175019 #22 Oct 13 2024 00:17:01
%S A175019 1,1,3,5,3,3,7,5,3,5,7,9,5,5,7,9,7,5,11,9,7,7,11,9,7,9,11,13,7,9,11,
%T A175019 13,9,9,11,13,11,9,15,13,11,9,15,13,11,11,15,13,11,13,15,17,11,13,15,
%U A175019 17,11,13,15,17,13,13,15,17,15,13,19,17,15,13,19,17,15,13,19,17,15,15,19,17
%N A175019 a(0)=a(1)=1; a(n) = a(n-a(n-2)) + 2.
%C A175019 Conjectures from _Chai Wah Wu_, Jun 12 2016: (Start)
%C A175019 All odd numbers appear in sequence.
%C A175019 2n+1 appears 2n+2 times.
%C A175019 a((n+3)^2-8) = 2n+1 is the last time 2n+1 appears.
%C A175019 For n > 0, a((n-1)^2+2) = 2n+1 is the first time 2n+1 appears. (End)
%H A175019 Seiichi Manyama, <a href="/A175019/b175019.txt">Table of n, a(n) for n = 0..10000</a>
%t A175019 a[0] = a[1] = 1; a[n_] := a[n] = a[n - a[n - 2]] + 2; Table[a[n], {n, 0, 200}]
%Y A175019 Cf. A028884.
%K A175019 nonn
%O A175019 0,3
%A A175019 _José María Grau Ribas_, Apr 04 2010