# the negation of $\preceq$

How do I type a modification of this $\npreccurlyeq$ symbol with not negated the above symbol, just negated the bottom one ?

Please note that I need the bottom part of the 2 symbols aligned with he curved upper part: it should not be straight.

Also I need both version of it: the curved single and double lines (so all of them negated).

• Clarification question: what exactly would be the meaning of these symbols? Aren't there other symbols available for such meanings? For example "smaller, but not equal" would just be <. – Marijn Apr 4 at 19:51
• @Marijn You are right, I need them just for pleasing my eye, in fact. And also for my curiosity if this could be done. The meaning may lie in the cooperative game theory. – user2925716 Apr 4 at 20:15
• As far as I know, the requested symbol does not exist; an appropriate name (it it did exist) would be \precncurlyeq. For best results, it should be (re)drawn based on the existing symbols that it is to accompany. (See also my comment on the answer by Sebastiano.) – barbara beeton Apr 5 at 0:56
• This symbol appears in txfonts, mathabx, and MnSymbol. The non-negated symbol also appears in fdsymbol, boisik, and stix. Since the symbol needs to be created from an existing symbol, the font you plan to use is important. – Sandy G Apr 5 at 2:49

Something like this using - it has been created the command \undernegpreccurlyeq:

\documentclass[border=2mm]{standalone}
\usepackage{mathabx}
\usepackage{scalerel}
\usepackage{graphicx}
\newcommand{\nback}[1][-.95pt]{
\mathrel{\raisebox{#1}{$\rotatebox[origin=c]{-315}{\scaleobj{0.55}{-}}$}}
}
\newcommand{\undernegpreccurlyeq}{%
\mathrel{\ooalign{$\preccurlyeq$\cr\kern1.2pt$\nback$}}}
\begin{document}
$\preccurlyeq, \undernegpreccurlyeq, a \undernegpreccurlyeq b$
\end{document}


Addendum on request from the user: You can use "for negated double line" the = symbol with a new symbol named \underdnegccurlyeq.

\documentclass[border=2mm]{standalone}
\usepackage{mathabx}
\usepackage{scalerel}
\usepackage{graphicx}
\newcommand{\nwback}[1][-.8pt]{
\mathrel{\raisebox{#1}{$\rotatebox[origin=c]{-310}{\scaleobj{0.55}{=}}$}}
}
\newcommand{\underdnegccurlyeq}{%
\mathrel{\ooalign{$\preccurlyeq$\cr\kern2pt$\nwback$}}}
\begin{document}
$\preccurlyeq, \underdnegccurlyeq, a \underdnegccurlyeq b$
\end{document}


• Although these look quite nice, I believe the orientation of the slash should be from right-to-left, not from left-to-right. Although I don't understand the difference in meaning, when I was researching the STIX symbols collection, I encountered an article where there were three distinct negations: backslash, vertical, forward slash. The traditional use of the forward slash to represent ordinary negation is, therefore, what I believe to be the preferred shape. – barbara beeton Apr 5 at 0:52
• @barbarabeeton Hi I totally accept your comment. When I write in the board the symbol \notin for example the negation bar is from right to left. I had created the code before I went to sleep. Thank you very much for the suggestion. – Sebastiano Apr 5 at 10:44
• @Sebastiano Looks great. Do you please also have an advice for negated double line as in your $$a\preceq b$$. I do not know even the unnegated case for this double line. Also, isn't there a LaTeX comman rather than TeX primitive for all of these ? – user2925716 Apr 5 at 12:57
• @user2925716 I hope to have understood your request adding another example. I suggest to read the comments of barbara beeton and Sandy G. Your symbols not exist and it is necessary (re)drawn based on the existing symbols. – Sebastiano Apr 5 at 15:37
• @Sebastiano You have actually doubled the other (wrong) symbol.Keep it but please add doubling the other one. – user2925716 Apr 5 at 17:34