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

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, 24, 30, 36, 40, 45, 48, 50, 60, 60, 70, 84, 105, 120, 140, 168, 180, 210, 240, 252, 280, 300, 315, 336, 350, 360, 420, 105, 120, 140, 168, 210, 240

Offset: 1

Author

Clark Kimberling, May 07 2006

Keywords

• nonn
• tabf

Comments

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).

Examples

			Row 4 is 12*(1/4, 1/3, 1/2, 2/3, 3/4, 1).
First 5 rows:
   1
   1  2
   2  3  4  6
   3  4  6  8  9 12
  12 15 20 24 30 36 40 45 48 60.
		

Crossrefs

Cf. A003418.