{"app":{"locale":"en-GB"},"problem":{"content":"

Let T(m, n) be the number of the binomial coefficients ⁱC_n that are divisible by 10 for n ≤ i < m(i, m and n are positive integers).
You are given that T(10⁹, 10⁷-10) = 989697000.

Find T(10¹⁸, 10¹²-10).

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