%@AUTEUR: Manuel Luque

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\psset{Decran=60}
\psset{SphericalCoor,viewpoint= 20 0 20}
%\psset{fontsize=3,numfaces=all}
\psframe(-6,-1)(6,7)
\pstVerb{/i 612 store}%
\defFunction{para}(u,v){2 u u mul mul 2 v v mul mul add}{}{}
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   r=1,
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   ngrid=.1 36,
   fcol=1 {i 1 i 35 add {/j exch def j (rouge)} for
           i 36 add 1 i 71 add {/j exch def j (blanc)} for 
           i 72 add 1 i 107 add {/j exch def j (bleu)} for
           /i i 108 add def} repeat
         0 1 611 {/i exch def i (blanc)} for]
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