This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A226212 #5 Dec 04 2016 19:46:31 %S A226212 1,1,2,1,2,1,3,4,4,3,5,5,4,6,6,5,5,7,7,7,6,8,8,8,8,7,7,7,9,9,9,9,9,8, %T A226212 8,10,10,10,10,10,10,9,9,9,9,9,11,11,11,11,11,11,11,11,10,10,10,12,12, %U A226212 12,12,12,12,12,12,12,12,11,11,11,11,11,11,11,11 %N A226212 Zeckendorf distance between n and floor(n/2). %C A226212 Zeckendorf distance is defined at A226207. %H A226212 Clark Kimberling, <a href="/A226212/b226212.txt">Table of n, a(n) for n = 1..1000</a> %e A226212 11 = 8 + 3 -> 5 + 2 -> 3 + 1 -> 2, and 5 -> 3 -> 2. The total number of Zeckendorf downshifts (i.e., arrows) is 5, so that a(11) = D(11,5) = 5. %t A226212 zeck[n_Integer] := Block[{k = Ceiling[Log[GoldenRatio, n*Sqrt[5]]], t = n, z = {}}, While[k > 1, If[t >= Fibonacci[k], AppendTo[z, 1]; t = t - Fibonacci[k], AppendTo[z, 0]]; k--]; If[n > 0 && z[[1]] == 0, Rest[z], z]]; d[n1_, n2_] := Module[{z1 = zeck[n1], z2 = zeck[n2]}, Length[z1] + Length[z2] - 2 (NestWhile[# + 1 &, 1, z1[[#]] == z2[[#]] &, 1, %t A226212 Min[{Length[z1], Length[z2]}]] - 1)]; lst = Map[d[#, Floor[#/2]] &, Range[100]] (* _Peter J. C. Moses_, May 30 2013 *) %Y A226212 Cf. A226080, A226207, A226211. %K A226212 nonn,easy %O A226212 1,3 %A A226212 _Clark Kimberling_, May 31 2013