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Some remarks on Kurepa's left factorial

Bernd C. Kellner
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Abstract

We establish a connection between the subfactorial function S(n) and the left factorial function of Kurepa K(n). Some elementary properties and congruences of both functions are described. Finally, we give a calculated distribution of primes below 10000 of K(n).

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Bernd C. Kellner. 2004-10-21. Some remarks on Kurepa's left factorial. https://arxiv.org/abs/math/0410477

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