login
A091092
In binary representation: minimal number of editing steps (delete, insert or substitute) to transform n into n^2.
4
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, 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, 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
OFFSET
0,4
COMMENTS
a(n) = A152487(A000290(n),n). - Reinhard Zumkeller, Dec 06 2008
LINKS
Eric Weisstein's World of Mathematics, Square Number
Eric Weisstein's World of Mathematics, Binary
FORMULA
a(n) = LevenshteinDistance(A007088(n), A001737(n)).
EXAMPLE
a(7)=3: 7->'111', 3 x insert a 0 between the last two 1's:
'110001'->49=7^2.
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Reinhard Zumkeller, Dec 18 2003
STATUS
approved