Hello,
I am making progress and I almost get what I want to achieve but I still have two problems :
how to color cells not containing numbers with the same color as the others ?
how to color in salmon, for example, cells 1 2  ?
                                                                     3
Thank you
Fabrice

\usecolors[X11]

\startuseMPgraphic{DiagonalRule}
  rulethickness := \frameddimension{rulethickness};

  drawoptions(
    withpen pencircle scaled rulethickness
    withcolor \MPcolor{\framedparameter{framecolor}});

  pair leftcorner, rightcorner;
  leftcorner  := (rulethickness, \overlayheight-rulethickness);
  rightcorner := (\overlaywidth-rulethickness, rulethickness);

  draw leftcorner -- rightcorner;
\stopuseMPgraphic

\defineoverlay
  [DiagonalRule]
  [\useMPgraphic{DiagonalRule}]

\define[2]\DiagonalLabel{%
  \setuptabulate [after={\blank[\frameddimension{offset}]}]
  \starttabulate [|p|r|]
    \NC    \NC #2 \NC\NR
    \NC #1 \NC    \NC\NR
  \stoptabulate
}


\starttext
\startluacode
   function Binom(n,k)
        if k > n then
             return ""
        elseif (n == 0 or k == 0) then
             return 1
        else
             return math.round((n*Binom(n-1,k-1))/k)
        end        
      end
  context.startxtable({"align={middle,lohi}, width=1cm,offset=0.8ex,bodyfont=9pt,framecolor=cyan"})
  context.startxrow()
  context.startxcell({"background=DiagonalRule,background=color,backgroundcolor=thistle2"})
  context("\\DiagonalLabel{\\m{n}}{\\m{k}}")
  context.stopxcell()
  for j = 0, 7 do
  context.startxcell({"background=color,backgroundcolor=thistle2"})
  context(j)
  context.stopxcell()
  end
  context.startxcell({"background=color,backgroundcolor=thistle2"})
  context("\\dots")
  context.stopxcell()
  context.stopxrow()
  for i = 0, 7 do
  context.startxrow()
  context.startxcell({"background=color,backgroundcolor=thistle2"})
  context(i)
  context.stopxcell()
  for j = 0, 8 do
  context.startxcell()
  context(Binom(i,j))
  context.stopxcell()
  end
  context.stopxrow()
  end
  context.startxrow()
  context.startxcell({"background=color,backgroundcolor=thistle2"})
  context("\\dots")
  context.stopxcell()
  for i = 0, 8 do
  context.startxcell({"background=color,backgroundcolor=thistle2"})
  context("")
  context.stopxcell()
  end
  context.stopxrow()
  context.stopxtable()
\stopluacode
\stoptext

Le lun. 20 juil. 2020 à 14:55, Hans Hagen <j.hagen@xs4all.nl> a écrit :
On 7/20/2020 2:40 PM, Jeong Dal wrote:

> I also wonder where is the boundary of ConTeXt.
The boundaries are set and shift by users (the mailing list) and
curiosity (personal).

Hans

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