View source for Graphic equality

A relation between two constructive objects (cf. [[Constructive object|Constructive object]]) which consists in the fact that the objects are constructed in the same way out of the same elementary tokens. Graphic equality of two words (cf. [[Word|Word]]) means that the words are composed of the same letters in the same sequence. Graphic equality of words may more precisely be formulated as follows: a) the empty word is graphically equal to itself only; b) two non-empty words <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/g/g045/g045020/g0450201.png" /> and <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/g/g045/g045020/g0450202.png" /> (where <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/g/g045/g045020/g0450203.png" /> and <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/g/g045/g045020/g0450204.png" /> denote the last letters of these words) are graphically equal if and only if <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/g/g045/g045020/g0450205.png" /> and <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/g/g045/g045020/g0450206.png" /> are graphically equal and the letters <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/g/g045/g045020/g0450207.png" /> and <img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/g/g045/g045020/g0450208.png" /> are identical. Graphic equality is usually denoted by the symbols

<table class="eq" style="width:100%;"> <tr><td valign="top" style="width:94%;text-align:center;"><img align="absmiddle" border="0" src="https://www.encyclopediaofmath.org/legacyimages/g/g045/g045020/g0450209.png" /></td> </tr></table>

====References====
<table><TR><TD valign="top">[1]</TD> <TD valign="top">  A.A. Markov,   "Theory of algorithms" , Israel Program Sci. Transl.  (1961)  (Translated from Russian)  (Also: Trudy Mat. Inst. Steklov. 42 (1954))</TD></TR><TR><TD valign="top">[2]</TD> <TD valign="top">  A.A. Markov,   N.M. [N.M. Nagornyi] Nagorny,   "The theory of algorithms" , Kluwer  (1988)  (Translated from Russian)</TD></TR></table>