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%I #10 Nov 11 2014 10:57:40
%S 1,2,4,7,11,17,26,37,52,70,92,120,157,200,254,323,401,490,597,719,859,
%T 1021,1211,1438,1687,1979,2325,2740,3183,3704,4262,4863,5553,6350,
%U 7201,8174,9216,10336,11545,12894,14350,15928,17646,19526,21596,23893,26352,29060,32060,35406,39167
%N a(1)=1, a(2)=2; thereafter a(n) = a(n-1) + a(n-1-(number of even terms so far)) + a(n-1-(number of odd terms so far)).
%C Suggested by A006336, A007604 and A249036-A249038.
%H Reinhard Zumkeller, <a href="/A249039/b249039.txt">Table of n, a(n) for n = 1..10000</a>
%F For n > 1: a(n+1) = a(n) + a(n - A249040(n)) + a(n - A249041(n)) by mutual recursion. - _Reinhard Zumkeller_, Nov 11 2014
%p M:=100;
%p v[1]:=1; v[2]:=2; w[1]:=0; w[2]:=1; x[1]:=1; x[2]:=1;
%p for n from 3 to M do
%p v[n]:=v[n-1]+v[n-1-w[n-1]]+v[n-1-x[n-1]];
%p if v[n] mod 2 = 0 then w[n]:=w[n-1]+1; x[n]:=x[n-1];
%p else w[n]:=w[n-1]; x[n]:=x[n-1]+1; fi;
%p od:
%p [seq(v[n], n=1..M)]; # A249039
%p [seq(w[n], n=1..M)]; # A249040
%p [seq(x[n], n=1..M)]; # A249041
%o (Haskell)
%o import Data.List (genericIndex)
%o a249039 n = genericIndex a249039_list (n - 1)
%o a249039_list = 1 : 2 : f 2 2 1 1 where
%o f x u v w = y : f (x + 1) y (v + 1 - mod y 2) (w + mod y 2)
%o where y = u + a249039 (x - v) + a249039 (x - w)
%o -- _Reinhard Zumkeller_, Nov 11 2014
%Y Cf. A006336, A007604, A249036, A249037, A249038.
%Y A249040 and A249041 give numbers of even and odd terms so far.
%K nonn
%O 1,2
%A _N. J. A. Sloane_, Oct 26 2014
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