Founded 2003 by Drew Sills and Doron Zeilberger.
Former co-organizers: Drew Sills (2003-2007), Moa ApaGodu (2005-2006), Lara Pudwell (2006-2008), Andrew Baxter (2008-2011), Brian Nakamura (2011-2013), Edinah Gnang (2011-2013), Matthew Russell (2013-2016), Nathan Fox (2016-2017), Bryan Ek (2017-2018), Mingjia Yang (2018-2020), Yonah Biers-Ariel (2018-2020), Robert Dougherty-Bliss (2020-2024), Stoyan Dimitrov (2023-2025)
Current co-organizers:
Doron Zeilberger (doronzeil {at} gmail [dot] com)
Aurora Hiveley (aurora.hiveley {at} scarletmail [dot] rutgers [dot] edu)
Lucy Martinez (lm1154 {at} scarletmail [dot] rutgers [dot] edu)
Archive of Previous Speakers and Talks You can find links to videos of some of these talks as well. Currently, our videos are being posted to our Vimeo page. Previously, we had videos posted on our YouTube page.
Date: Thu., Sept. 10, 2026, 5:00pm (Eastern Time)
Zoom Link [password: The 20th Catalan number, alias (40)!/(20!*21!), alias 6564120420 ]
Speaker: Neil Sloane, The OEIS Foundation and Rutgers University.
Title: Highlights from the First 400,000 Sequences in the OEIS
Abstract: The OEIS should reach 400,000 sequences in the next two months, so it seems appropriate to review some of the highlights of the database as well as some current hot topics. I'll mention the shortest and the longest finite sequences (think Goodstein), the scariest, the most musical, the best rug design, the most wanted primes, the most potentially rewarding sequences, etc. Concerning current sequences, there are the best and the worst contributions from AI, and the handful of sequences I would most like to solve.
Date: Thu., Sept. 17, 2026, 5:00pm (Eastern Time)
Zoom Link [password: The 20th Catalan number, alias (40)!/(20!*21!), alias 6564120420 ]
Speaker:
Thotsaporn "Aek" Thanatipanonda, Mahidol University International College in Thailand.
Title: Double Deficiencies in Permutations With and Without Pattern Avoidance
Abstract:A double deficiency (DD) of a permutation π of length n is an index k, where 1 ≤ k ≤ n, satisfying π(k) < k < π-1(k). In this talk, we investigate the distribution of the number of double deficiencies in both unrestricted permutations and length-3 pattern-avoiding permutations.
Date: Thu., Sept. 24, 2026, 5:00pm (Eastern Time)
Zoom Link [password: The 20th Catalan number, alias (40)!/(20!*21!), alias 6564120420 ]
Speaker: Victor Miller, SRI and Anduril Industries
Title: Resolving the Hypercube
Abstract: The metric dimension of the hypercube is the smallest cardinality of a set, S, of n dimensional 0/1 vectors so that any two distinct 0/1 vectors have different Hamming distances to some member of S. This problem was first treated ("Problem B") in a paper of Erdos-Renyi ("Two Problems in Information Theory") where it is closely connected with the coin weighing problem of Soderberg-Shapiro ("Problem A"). Using the probabilistic method they gave a lower bound, which combined with later explicit constructions by Cantor-Mills and Lindstrom give tight asymptotics. However finding the exact value has been challenging. It is detailed in OEIS sequence A303735. There have a been a number of papers devoted to this problem, but almost all of them use heuristic search to find smaller sized sets S than those given by the explicit constructions, and do not deal with certifying that the set, S, is minimal.
In this talk I'll discuss the use of SAT solvers which allowed calculation of three new values using the CEGAR (counter-example guided abstraction refinement) method. In the course of this investigation a number of auxilliary problems arose: (1) Using a refinement of entropy inequalities of Pippenger to drastically cut down on the number of cases needed to be handled. (2) A related problem of finding the minimum subset of 0/1 vectors required in order to certify a minimal S. (3) Giving short "certificates" asserting that the computation is correct.
Date: Thu., Oct. 1, 2026, 5:00pm (Eastern Time)
Zoom Link [password: The 20th Catalan number, alias (40)!/(20!*21!), alias 6564120420 ]
Speaker: Michael Milgram
Title: tbd
Abstract: tbd
Date: Thu., Oct. 8, 2026, 5:00pm (Eastern Time)
Zoom Link [password: The 20th Catalan number, alias (40)!/(20!*21!), alias 6564120420 ]
Speaker: Benoit Cloitre (independent researcher)
Title: tbd
Abstract: tbd
Date: Thu., Oct. 15, 2026, 5:00pm (Eastern Time)
Zoom Link [password: The 20th Catalan number, alias (40)!/(20!*21!), alias 6564120420 ]
Speaker: Robert Laniewski
Title: Why the Riemann hypothesis is ill-posed
Abstract: By constructing custom "chimera" functions from Dirichlet L-functions, we create self-dual test objects whose true zero distributions are independently verifiable through contour counts using the argument principle. When standard critical-line verification algorithms are run on these self-dual chimeras, we discover a remarkable phenomenon. The line instrument is exact on the critical line, but it remains entirely silent regarding zeros sitting beside it. An unbroken sequence of on-line findings is precisely what a line-restricted instrument returns, whether the adjacent strip is empty or not. In the second half of the talk, we will trace this structural failure of verification back to its logical origins, and re-examine five historical proofs of the Prime Number Theorem. We will see how classical proofs by contradiction in analytic number theory rely on an unexamined 1905 convention of logic, where a failure of the analytic language to form a valid term around an off-line zero is conflated with a logical refutation
Date: Thu., Oct. 22, 2026, 5:00pm (Eastern Time)
Zoom Link [password: The 20th Catalan number, alias (40)!/(20!*21!), alias 6564120420 ]
Speaker: Jaideep Sai Padhi, Purdue University (Freshman)
Title: How I used Claude to meet Numerous Challenges Posed by Doron Zeilberger, thereby making the OEIS 1000 dollars Richer
Abstract: I will describe how I used Claude (Fable/Opus) to meet some very hard challenges posed by Dr. Z., for which he offered donations to the OEIS in honor of the first prover/disprover.
Date: Thu., Oct. 29 2026, 5:00pm (Eastern Time)
Zoom Link [password: The 20th Catalan number, alias (40)!/(20!*21!), alias 6564120420 ]
Speaker: Nikolai Beluhov, Cambridge University
Title: Bootstrap Percolation and Partial Difference Equations
Abstract: We study a bootstrap percolation process on the integer lattice where each newly occupied point completes a copy of one of the patterns in some fixed collection. We aim, given this collection, to find the smallest size of a percolating seed. We show that, for two patterns in two dimensions, in essence the answer is given by the mixed volume of the patterns' convex hulls. Our motivation for studying this setup comes from the theory of partial difference equations. Conversely, our considerations yield one consistency criterion for systems of two partial difference equations in two dimensions
Date: Thu., Nov. 5, 2026, 5:00pm (Eastern Time)
Zoom Link [password: The 20th Catalan number, alias (40)!/(20!*21!), alias 6564120420 ]
Speaker: tbd
Title: tbd
Abstract: tbd
Date: Thu., Nov. 12, 2026, 5:00pm (Eastern Time)
Zoom Link [password: The 20th Catalan number, alias (40)!/(20!*21!), alias 6564120420 ]
Speaker: tbd
Title: tbd
Abstract: tbd
Date: Thu., Nov. 19, 2026, 5:00pm (Eastern Time)
Zoom Link [password: The 20th Catalan number, alias (40)!/(20!*21!), alias 6564120420 ]
Speaker: tbd
Title: tbd
Abstract: tbd
Date: Thu., Dec. 3, 2026, 5:00pm (Eastern Time)
Zoom Link [password: The 20th Catalan number, alias (40)!/(20!*21!), alias 6564120420 ]
Speaker: tbd
Title: tbd
Abstract: tbd
Date: Thu., Dec. 10, 2026, 5:00pm (Eastern Time)
Zoom Link [password: The 20th Catalan number, alias (40)!/(20!*21!), alias 6564120420 ]
Speaker: tbd
Title: tbd
Abstract: tbd