login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A112964
Sum(mu(i)*sigma(j): i+j=n), with mu=A008683 and sigma=A000203.
5
0, 1, 2, 0, 0, -6, -3, -12, -11, -13, -22, -19, -20, -30, -41, -15, -55, -24, -52, -41, -59, -24, -109, -22, -78, -42, -111, -26, -131, -2, -119, -75, -133, -8, -214, 7, -175, -68, -176, -17, -209, 14, -231, -73, -175, 45, -349, -11, -236, -20, -236, -53, -384, 68, -321, -56, -270, 1, -457, 41, -328, -48
OFFSET
1,3
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
EXAMPLE
a(5)=mu(1)*sigma(4)+mu(2)*sigma(3)+mu(3)*sigma(2)+mu(4)*sigma(1)
= 1*7 - 1*4 - 1*3 + 0*1 = 0.
PROG
(PARI) a(n)=sum(i=1, n-1, moebius(i)*sigma(n-i)) \\ Charles R Greathouse IV, Feb 14 2013
KEYWORD
sign
AUTHOR
Reinhard Zumkeller, Oct 07 2005
STATUS
approved