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In binary representation: minimal number of editing steps (delete, insert or substitute) to transform n into n^2.
4

%I #15 Dec 02 2018 11:00:44

%S 0,0,1,2,2,2,3,3,3,3,3,4,4,4,4,4,4,4,4,4,4,4,5,6,5,5,5,5,5,5,5,5,5,5,

%T 5,5,5,5,5,6,5,5,5,6,6,6,7,7,6,6,6,6,6,6,6,7,6,6,6,6,6,6,6,6,6,6,6,6,

%U 6,6,6,6,6,6,6,7,6,6,7,7,6,6,6,6,6,7,7,7,7,6,7,8,8,7,8,8,7,7,7,7,7,8

%N In binary representation: minimal number of editing steps (delete, insert or substitute) to transform n into n^2.

%C a(n) = A152487(A000290(n),n). - _Reinhard Zumkeller_, Dec 06 2008

%H Alois P. Heinz, <a href="/A091092/b091092.txt">Table of n, a(n) for n = 0..20000</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/SquareNumber.html">Square Number</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Binary.html">Binary</a>

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Levenshtein_distance">Levenshtein Distance</a>

%H <a href="/index/Bi#binary">Index entries for sequences related to binary expansion of n</a>

%F a(n) = LevenshteinDistance(A007088(n), A001737(n)).

%e a(7)=3: 7->'111', 3 x insert a 0 between the last two 1's:

%e '110001'->49=7^2.

%Y Cf. A091093, A091091, A070939, A000290.

%K nonn,base

%O 0,4

%A _Reinhard Zumkeller_, Dec 18 2003