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%I #20 Jun 02 2022 10:25:55
%S 1,4,6,12,20,24,24,48,72,120,120,120,120,168,120,240,240,360,360,360,
%T 360,360,360,720,720,720,720,1008,1008,720,720,720,720,720,1680,2520,
%U 2520,2520,2520,1440,1440,2520,2520,2520,2520,2520,2520,5040,5040,5040
%N Largest of the most frequently occurring numbers in 1-to-n multiplication cube.
%H Branden Aldridge, <a href="/A057339/b057339.txt">Table of n, a(n) for n = 1..500</a>
%e 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, each occurring 15 times. The largest of these numbers is 24, so a(7) = 24.
%o (Java)
%o public class LargestMultCube {
%o static int high, highestFrequency = 0;
%o static int[] counters;
%o public static void main(String[] args) {
%o int max=500;
%o counters = new int[max*max*max+1];
%o for(int outer=1; outer<=max; outer++) {
%o tally(outer*outer*outer, 1);
%o for(int middle=outer-1; middle>=1; middle--) {
%o tally(outer*outer*middle, 3); tally(outer*middle*middle, 3);
%o for(int inner=middle-1; inner>=1; inner--) {
%o tally(outer*middle*inner, 6); } }
%o System.out.println(outer+" "+high); } }
%o private static void tally(int number, int repeatFactor) {
%o counters[number] += repeatFactor;
%o if(counters[number] >= highestFrequency) {
%o if (counters[number] == highestFrequency)
%o if (number > high) high = number;
%o if (counters[number] > highestFrequency) {
%o highestFrequency = counters[number]; high = number; } } } }
%o // _Branden Aldridge_, Apr 15 2022
%Y Cf. A057143, A057338, A057342, A057345.
%K nonn
%O 1,2
%A _Neil Fernandez_, Aug 28 2000
%E More terms from _David W. Wilson_, Aug 28 2001
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