Duadesgon

Duadesgon or 20gon is figura har 20 gono ji 20 comen.

Meter

Moyun gono de pinpan duadesgon hare 162° ji oto maxuscu cel 3240°.

Peryaje

Peryaje de pinpan duadesgon har comenli lungoje a is:

${\text{Peryaje}}=5a^{2}(1+{\sqrt {5}}+{\sqrt {5+2{\sqrt {5}}}}).$

Misal

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  Duadesgonli kostruixey in Usa (le kostrui fe 1903)