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 A064048 Number of most frequently occurring numbers in the 1-to-n multiplication table. 2
 1, 1, 3, 1, 1, 2, 2, 4, 5, 9, 9, 2, 2, 2, 4, 5, 5, 1, 1, 1, 1, 1, 1, 5, 5, 5, 5, 7, 7, 2, 2, 2, 2, 2, 2, 4, 4, 4, 4, 1, 1, 1, 1, 1, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4, 4, 6, 6, 6, 6, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 6, 6, 1, 1, 1, 1, 1, 1, 1, 1, 3, 3, 3, 3, 6, 6, 6, 6, 6, 6, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS Branden Aldridge, Table of n, a(n) for n = 1..20000 EXAMPLE In the 1-to-6 multiplication table, the most frequently occurring numbers (each occurring 4 times) are 6 and 12. Therefore a(6)=2. MATHEMATICA mfon[n_]:=Module[{x=SortBy[Tally[Times@@@Tuples[Range[n], 2]], Last]}, Length[ Select[x, #[[2]]==x[[-1, 2]]&]]]; Array[mfon, 100] (* Harvey P. Dale, Oct 20 2012 *) PROG (PARI) a(n)=my(v=List(), ct, s, r, t); for(a=1, n, for(b=1, n, listput(v, a*b))); s=Set(v); for(i=1, #s, t=sum(j=1, #v, v[j]==s[i]); if(tr, ct=1; r=t, ct++)); ct \\ Charles R Greathouse IV, Feb 05 2022 CROSSREFS Cf. A064047, A057142, A057143, A057144. Sequence in context: A352935 A364757 A204253 * A336218 A016464 A245570 Adjacent sequences: A064045 A064046 A064047 * A064049 A064050 A064051 KEYWORD nonn AUTHOR Matthew Somerville (matthew.somerville(AT)trinity.oxford.ac.uk), Aug 24 2001 STATUS approved

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Last modified November 29 15:54 EST 2023. Contains 367445 sequences. (Running on oeis4.)