Further Improvements of Lower Bounds for the Least Common Multiples of Arithmetic Progressions

Shaofang  Hong; Scott Duke Kominers

Article | Proceedings of the American Mathematical Society | March 2010

Further Improvements of Lower Bounds for the Least Common Multiples of Arithmetic Progressions

by Shaofang Hong and Scott Duke Kominers

Abstract

For relatively prime positive integers u_0 and r, we consider the arithmetic progression {u_k := u_0+k*r} (0 <= k <= n). Define L_n := lcm{u_0,u_1,...,u_n} and let a >= 2 be any integer. In this paper, we show that, for integers alpha,r >= a and n >= 2*alpha*r, we have L_n >= u_0*r^{alpha+a-2}*(r+1)^n. In particular, letting a = 2 yields an improvement to the best previous lower bound on L_n (obtained by Hong and Yang) for all but three choices of alpha,r >= 2.

Keywords: Mathematical Methods;

Format: Print

5 pages

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Citation:

Hong, Shaofang, and Scott Duke Kominers. "Further Improvements of Lower Bounds for the Least Common Multiples of Arithmetic Progressions." Proceedings of the American Mathematical Society 138, no. 3 (March 2010): 809–813.

This paper develops a class of equilibrium-independent predictions of competitive equilibrium with indivisibilities. Specifically, we prove an analogue of the “Lone Wolf Theorem” of classical matching theory, showing that when utility is perfectly transferable, any agent who does not participate in trade in one competitive equilibrium must receive her autarky payoff in every competitive equilibrium. Our results extend to approximate equilibria and to settings in which utility is only approximately transferable.

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Further Improvements of Lower Bounds for the Least Common Multiples of Arithmetic Progressions

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