cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A118975 Triangular array: row n consists of M times n-th-order Farey fractions, where M is the LCM of their denominators.

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%I A118975 #9 Mar 17 2018 21:15:20
%S A118975 1,1,2,2,3,4,6,3,4,6,8,9,12,12,15,20,24,30,36,40,45,48,60,10,12,15,20,
%T A118975 24,30,36,40,45,48,50,60,60,70,84,105,120,140,168,180,210,240,252,280,
%U A118975 300,315,336,350,360,420,105,120,140,168,210,240
%N A118975 Triangular array: row n consists of M times n-th-order Farey fractions, where M is the LCM of their denominators.
%C A118975 The multiplier M(n) = A003418(n). Column 1 is A002944(n) = (1/n)*lcm(1,2,...,n). The numbers in row n are relatively prime (unlike the related array A093594).
%e A118975 Row 4 is 12*(1/4, 1/3, 1/2, 2/3, 3/4, 1).
%e A118975 First 5 rows:
%e A118975    1
%e A118975    1  2
%e A118975    2  3  4  6
%e A118975    3  4  6  8  9 12
%e A118975   12 15 20 24 30 36 40 45 48 60.
%Y A118975 Cf. A003418.
%K A118975 nonn,tabf
%O A118975 1,3
%A A118975 _Clark Kimberling_, May 07 2006