The v-number of binomial edge ideals

Abstract

The invariant v-number was introduced very recently in the study of Reed-Muller-type codes. Jaramillo and Villarreal (J. Combin. Theory Ser. A 177:105310, 2021) initiated the study of the v-number of edge ideals. Inspired by their work, we take the initiation to study the v-number of binomial edge ideals in this paper. We discuss some properties and bounds of the v-number of binomial edge ideals. We explicitly find the v-number of binomial edge ideals locally at the associated prime corresponding to the cutset θ. We show that the v-number of Knutson binomial edge ideals is less than or equal to the v-number of their initial ideals. Also, we classify all binomial edge ideals whose v-number is 1. Moreover, we try to relate the v-number with the Castelnuvo-Mumford regularity of binomial edge ideals and give a conjecture in this direction.