This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A057143 #19 Mar 29 2022 08:36:41 %S A057143 1,2,6,4,4,12,12,24,24,40,40,24,24,24,60,60,60,36,36,60,60,60,60,120, %T A057143 120,120,120,168,168,120,120,120,120,120,120,180,180,180,180,120,120, %U A057143 120,120,120,360,360,360,360,360,360,360,360,360,360,360,360,360,360 %N A057143 Largest of the most frequently occurring numbers in 1-to-n multiplication table. %H A057143 Branden Aldridge, <a href="/A057143/b057143.txt">Table of n, a(n) for n = 1..20000</a> (first 1000 terms from Reinhard Zumkeller). %e A057143 M(n) is the array in which m(x,y)= x*y for x = 1 to n and y = 1 to n. In M(10), the most frequently occurring numbers are 6, 8, 10, 12, 18, 20, 24, 30,40, each occurring 4 times. The largest of these numbers is 40, so a(10) = 40. %o A057143 (Haskell) %o A057143 import Data.List (group, sort, sortBy) %o A057143 import Data.Function (on) %o A057143 a057143 n = head $ head $ reverse $ sortBy (compare `on` length) $ %o A057143 group $ sort [u * v | u <- [1..n], v <- [1..n]] %o A057143 -- _Reinhard Zumkeller_, Jun 22 2013 %Y A057143 Cf. A057142, A057144, A057338. %K A057143 nonn %O A057143 1,2 %A A057143 _Arran Fernandez_, Aug 13 2000 %E A057143 More terms from Larry Reeves (larryr(AT)acm.org), Apr 18 2001