A near-repunit is an integer kRn that has n - 1 digits equal to 1, and one 0 in the k +
Chapter 16, Problem 48(choose chapter or problem)
A near-repunit is an integer kRn that has n - 1 digits equal to 1, and one 0 in the k + 1 'stplace from the right; that is,kRn = Rn-k-1 lOk+l + Rk = 111 ... 11011 ... 111Show that if gcd(n - 1, 3k) > 1, then k Rn is composite
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