100,101,110,112,113,114,115,116,117,118,119,121,122,131,133,141,144,151,155,161,166,171,177,181,188,191,199
De la 100 la 200= 27 nr
De la 200 la 300=27 nr
300-400=27
400-500=27.....si tot asa pana la 1000
27•9= 243 nr care au exact 2 cifre identice
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