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%I #11 Mar 30 2012 17:34:13
%S 1,1,2,2,3,4,4,4,5,6,7,7,8,8,8,8,9,10,11,12,13,13,14,14,15,15,15,16,
%T 16,16,16,16,17,18,19,20,21,22,23,23,24,24,25,26,27,26,27,28,28,29,30,
%U 29,30,30,31,31,31,31,32,32,32,32,32,32,33,34,35,36,37,38,39,40,41,41,42
%N a(n) = a((a(n-2))*mod(n,2)+a(n-1)*(1-mod(n,2))) + a((n - a(n-2))*mod(n,2)+(n-a(n-1))*(1-mod(n,2))).
%C Let M = A005229, C = A004001. Then we may define a pair of new sequences by o1 = M*mod(n,2)+C*(1-mod(n,2)) (this sequence), o2 = C*mod(n,2)+M*(1-mod(n,2)) (A086525 - or is it A086335?).
%H <a href="/index/Ho#Hofstadter">Index entries for Hofstadter-type sequences</a>
%t digits = 200 Mc[n_Integer?Positive] := Mc[n] = Mc[( Mc[n-2])*(Mod[n, 2])+Mc[n-1]*(1-Mod[n, 2])] + Mc[(n - Mc[n-2])*(Mod[n, 2])+(n-Mc[n-1])*(1-Mod[n, 2])] Mc[1] = Mc[2] = 1 a1=Table[Mc[n], {n, 1, digits}]
%Y Cf. A005229, A086525, A086335. Different from A004001.
%K nonn
%O 1,3
%A _Roger L. Bagula_, Sep 15 2003
%E Edited by _N. J. A. Sloane_, Nov 07 2007