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A064048 Number of most frequently occurring numbers in the 1-to-n multiplication table. 1
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

Table of n, a(n) for n=1..100.

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 *)

CROSSREFS

Cf. A064047, A057142, A057143, A057144.

Sequence in context: A301330 A175636 A204253 * A016464 A245570 A243925

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 May 19 17:48 EDT 2019. Contains 323395 sequences. (Running on oeis4.)