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A249309 First row of spectral array W(Pi/2).

%I A249309 #7 Oct 25 2014 05:08:41
%S A249309 1,2,3,5,7,13,20,35,54,96,150,264,414,726,1140,1997,3136,5495,8631,
%T A249309 15121,23752,41612,65363,114513,179876,315132,495008,867223,1362230,
%U A249309 2386544,3748774,6567622,10316396
%N A249309 First row of spectral array W(Pi/2).
%H A249309 A. Fraenkel and C. Kimberling, <a href="http://dx.doi.org/10.1016/0012-365X(94)90259-3">Generalized Wythoff arrays, shuffles and interspersions</a>, Discrete Mathematics 126 (1994) 137-149.
%o A249309 (PARI)
%o A249309 \\ The first row of the generalized Wythoff array W(h),
%o A249309 \\   where h is an irrational number between 1 and 2.
%o A249309 row1(h, m) = {
%o A249309   my(
%o A249309     a=vector(m, n, floor(n*h)),
%o A249309     b=setminus(vector(m, n, n), a),
%o A249309     w=[a[1]^2, b[a[1]]],
%o A249309     j=3
%o A249309   );
%o A249309   while(1,
%o A249309     if(j%2==1,
%o A249309       if(w[j-1]<=#a, w=concat(w, a[w[j-1]]), return(w))
%o A249309     ,
%o A249309       if(w[j-2]<=#b, w=concat(w, b[w[j-2]]), return(w))
%o A249309     );
%o A249309     j++
%o A249309   );
%o A249309   w
%o A249309 }
%o A249309 allocatemem(10^9)
%o A249309 row1(Pi/2, 10^7)
%Y A249309 Cf. A007068, A022159, A022161, A022163, A022165.
%K A249309 nonn
%O A249309 1,2
%A A249309 _Colin Barker_, Oct 25 2014