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A062859 Size of smallest triangular multiplication table which contains some number n times.

%I A062859 #10 Oct 16 2023 23:30:06
%S A062859 1,4,12,18,30,40,60,72,90,120,140,168,180,210,252,280,315,336,360,420,
%T A062859 504,560,630,672,720,792,840,924,990,1008,1155,1232,1260,1320,1386,
%U A062859 1540,1584,1680,1848,1980,2016,2310,2376,2520,2640,2772,2970,3024,3080
%N A062859 Size of smallest triangular multiplication table which contains some number n times.
%e A062859 a(4)=18 because the size-18 triangular multiplication table is the smallest to contain a particular number 4 times (namely the number A062858(4)=36).
%o A062859 (Python)
%o A062859 from itertools import count
%o A062859 from collections import Counter
%o A062859 def A062859(n):
%o A062859     c = Counter()
%o A062859     for m in count(1):
%o A062859         for i in range(1,m+1):
%o A062859             ij = i*m
%o A062859             c[ij] += 1
%o A062859             if c[ij]>=n:
%o A062859                 return m # _Chai Wah Wu_, Oct 16 2023
%Y A062859 The least such number is A062858(n).
%Y A062859 Cf. A027424, A062851, A062854, A062855, A062856, A062857, A062858, A000217.
%K A062859 nonn
%O A062859 1,2
%A A062859 Ron A. Lalonde (ronronronlalonde(AT)hotmail.com), Jun 25 2001
%E A062859 More terms from _Don Reble_, Nov 08 2001