id:A060841 - OEIS Search Results

Search: id:A060841

Displaying 1-1 of 1 results found.

page 1

1/det(M) where M is the n X n matrix with M[i,j]= 1/lcm(i,j).

+0
1

1, 4, 18, 144, 900, 16200, 132300, 2116800, 28576800, 714420000, 8644482000, 311201352000, 4382752374000, 143169910884000, 4026653743612500, 128852919795600000, 2327405863808025000, 125679916645633350000 (list; graph; listen)

	OFFSET	`1,2`
	FORMULA	`a(n) = (n!)^2 / (phi(1)phi(2)...*phi(n)) = (n!)^2 / A001088(n)`
	EXAMPLE	`a(2) = 4 because the matrix M is: [1,1/2; 1/2,1/2] and det(M) = 1/4`
	CROSSREFS	`A001088, A000010, A060238.` `Sequence in context: A001423 A034517 A065857 this_sequence A059837 A054759 A007153` `Adjacent sequences: A060838 A060839 A060840 this_sequence A060842 A060843 A060844`
	KEYWORD	`nonn,easy`
	AUTHOR	`Noam Katz (noamkj(AT)hotmail.com), May 02 2001`
	EXTENSIONS	`More terms from Reiner Martin (reinermartin(AT)hotmail.com), May 17 2001`

page 1

Search completed in 0.002 seconds

Last modified September 7 23:08 EDT 2008. Contains 143486 sequences.

AT&T Labs Research