OFFSET
1,2
COMMENTS
a(n) is also the determinant of the symmetric n X n matrix M defined by M(i,j) = A060648(gcd(i,j)) for 1 <= i,j <= n, note that A060648 is the Inverse Möbius transform of A001615. - Enrique Pérez Herrero, Aug 12 2011
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..423
Antal Bege, Hadamard product of GCD matrices, Acta Univ. Sapientiae, Mathematica, 1, 1 (2009) 43-49
Eric Weisstein's World of Mathematics, Le Paige's Theorem
MAPLE
A175836 := proc(n) option remember; local p; `if`(n<2, 1, n*mul(1+1/p, p=factorset(n))*A175836(n-1)) end: # Peter Luschny, Feb 28 2014
MATHEMATICA
JordanTotient[n_, k_:1]:=DivisorSum[n, #^k*MoebiusMu[n/# ]&]/; (n>0)&&IntegerQ[n];
DedekindPsi[n_]:=JordanTotient[n, 2]/EulerPhi[n];
A175836[n_]:=Times@@DedekindPsi/@Range[n]
PROG
(PARI) a=direuler(p=2, 100, (1+X)/(1-p*X)); for(i=2, #a, a[i]*=a[i-1]); a
\\ Charles R Greathouse IV, Jul 29 2011
(Haskell)
a175836 n = a175836_list !! (n-1)
a175836_list = scanl1 (*) a001615_list
-- Reinhard Zumkeller, Mar 01 2014
CROSSREFS
KEYWORD
nonn
AUTHOR
Enrique Pérez Herrero, Sep 18 2010
STATUS
approved