solved добавяме най-малката ненулева цифра

Дадена е редица, на която първият член е $1$, а всеки следващ се получава като към предишния се добави най-малката му ненулева цифра. Да се определи колко цифри има числото на позиция $9\cdot 1000^{1000}$

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