English

Variations of Lucas' Theorem Modulo Prime Powers

Number Theory 2013-01-03 v1

Abstract

Let pp be a prime, and let k,n,m,n0k,n,m,n_0 and m0m_0 be nonnegative integers such that k1k\ge 1, and 0_0 and m0m_0 are both less than pp. K. Davis and W. Webb established that for a prime p5p\ge 5 the following variation of Lucas' Theorem modulo prime powers holds (npk+n0mpk+m0)(np(k1)/3mp(k1)/3)(n0m0)(modpk). {np^k +n_0 \choose mp^k+m_0}\equiv{np^{\lfloor(k-1)/3\rfloor} \choose mp^{\lfloor(k-1)/3\rfloor}} {n_0 \choose m_0} \pmod{p^k}. In the proof the authors used their earlier result that present a generalized version of Lucas' Theorem. In this paper we present a a simple inductive proof of the above congruence. Our proof is based on a classical congruence due to Jacobsthal, and we additionally use only some well known identities for binomial coefficients. Moreover, we prove that the assertion is also true for p=2p=2 and p=3p=3 if in the above congruence one replace (k1)/3\lfloor(k-1)/3\rfloor by k/2\lfloor k/2\rfloor, and by (k1)/2\lfloor (k-1)/2\rfloor, respectively. As an application, in terms of Lucas' type congruences, we obtain a new characterization of Wolstenholme primes.

Keywords

Cite

@article{arxiv.1301.0252,
  title  = {Variations of Lucas' Theorem Modulo Prime Powers},
  author = {Romeo Mestrovic},
  journal= {arXiv preprint arXiv:1301.0252},
  year   = {2013}
}

Comments

11 pages

R2 v1 2026-06-21T23:02:57.587Z