History
All 17 groups were used by Egyptian craftsmen, and used extensively in the Muslim world. A proof that there were only 17 possible patterns was first carried out by Evgraf Fedorov in 1891 and then derived independently by George Pólya in 1924.
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“It is remarkable how closely the history of the apple tree is connected with that of man.”
—Henry David Thoreau (1817–1862)