Status
On this page
Status
Topics
Status
On this page
Status
Topics
For we define the deficiency of as follows. If is divisible by a prime then the deficiency is undefined. Otherwise, the deficiency is the number of such that is -smooth, that is, divisible only by primes .
Are there infinitely many binomial coefficients with deficiency ? Are there only finitely many with deficiency ?
Source: erdosproblems.com/1093
No claim settles this problem.
Open: the site's label (page last edited 27 December 2025). The site's commentary credits Kevin Barreto's thread post of 16 December 2025 with a conditional answer to the second question. The post assumes two conjectures. The first strengthens the Lagarias--Soundararajan conjecture: for some and every , only finitely many coprime have every prime factor of below . The second is a lower bound , with and all large , on the least at which has deficiency at least , when such an exists. From these the post proves that only finitely many with have deficiency at least . A conditional thread post, it has no claim page.