A057338 Occurrences of most frequently occurring number in 1-to-n multiplication cube.
1, 3, 6, 9, 9, 15, 15, 21, 24, 24, 24, 36, 36, 36, 48, 51, 51, 57, 57, 75, 75, 75, 75, 90, 90, 90, 90, 90, 90, 114, 114, 114, 114, 114, 126, 138, 138, 138, 138, 156, 156, 180, 180, 180, 198, 198, 198, 207, 207, 207, 207, 207, 207, 207, 207, 237, 237, 237, 237, 267
Offset: 1
Examples
M(n) is the array in which m(x,y,z)=x*y*z for x = 1 to n, y = 1 to n and z = 1 to n. In M(7) the most frequently occurring numbers are 12 and 24. They occur 15 times, so a(7) = 15.
Links
- David A. Corneth, Table of n, a(n) for n = 1..10000 (first 250 terms from Reinhard Zumkeller, terms 251..500 from Branden Aldridge).
Programs
-
Haskell
import Data.List (group, sort) a057338 n = head $ reverse $ sort $ map length $ group $ sort [u * v * w | u <- [1..n], v <- [1..n], w <- [1..n]] -- Reinhard Zumkeller, Jun 22 2013
Extensions
More terms from David W. Wilson, Aug 28 2001