portrait of cahit arf, arf invariant, arithmetic series, abacus and binary sequence from turkish ten lira banknote

devaluation arithmetic background invariant financial inflation recession banknotes portrait sequence banknote currency exchange commerce monetary business tafrac14 turkish finance economy ataturk country closeup turkiye series abacus binary turkey europe crisis design cahit money color trade front paper liras close rkiye lira cash bill turk bank note arf pay