OFFSET
1,3
LINKS
Enrique PĂ©rez Herrero, Table of n, a(n) for n = 1..100
PROG
(Sage)
def A060239(n):
P = Matrix(lambda i, j: lcm(i+1, j+1), nrows=n)
Q = Matrix(lambda i, j: gcd(i+1, j+1), nrows=n)
return (P*Q).det()/factorial(n) # D. S. McNeil, Jan 16 2011
CROSSREFS
KEYWORD
sign
AUTHOR
MCKAY john (mckay(AT)cs.concordia.ca), Mar 21 2001
STATUS
approved