MacMahon, Percy Alexander, 1854-1929 · Cambridge [Eng.] The University press · leaf 27
NE W MA THEM A TIC A L PAS TIMES 12 We have now four types : Colours i 2 O 4 2 3 2 4 6 I and varieties as usual. Examples are given in fig. 12. An example of every type is given as an indication that probably in other pastimes all types are possible. The reader however will notice that other… … C2.1 B2,2,4 C2,i Bi,i,6 Fig. 1: 8. In the case of the remaining contact system Ci,2, viz. 1 to 1 and 2 to 3, we find colour 1 must occur an uneven number of times upon the boundary while colour 2, since it occurs inside just as often as colour 3, must occur three more times on the boundary than…
Mathematical recreations
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![An illustration from Divina proportione : opera a tutti glingegni perspicaci e curiosi necessaria oue ciascun studioso di philosophia: prospettiua pictura sculptura: architectura: musica: e altre mathematice: suavissima: sotile: e admirabile doctrina consequira: e delecterassi: co[n] varie questione de secretissima scientia (1509)](https://img.insideoutlibrary.com/img/200/ia-divinaproportion00paci-106-264.webp)
