A112962 Sum(mu(i)*phi(j): i+j=n), with mu=A008683 and phi=A000010.

0, 1, 0, 0, -1, -1, -4, -2, -5, -8, -5, -8, -9, -11, -10, -24, 1, -21, -11, -23, -15, -37, 4, -42, -11, -38, -7, -49, 6, -63, -12, -44, -3, -81, 10, -106, 7, -49, -8, -92, 15, -103, 2, -72, -5, -114, 41, -140, -3, -114, 8, -113, 49, -179, 3, -135, 27, -131, 46, -218, -7, -99, 32, -185, 72, -259, 50, -104, 23, -211, 52, -248, 43, -153

Offset: 1

Author

Reinhard Zumkeller, Oct 07 2005

Keywords

• sign

Examples

			a(5)=mu(1)*phi(4)+mu(2)*phi(3)+mu(3)*phi(2)+mu(4)*phi(1) = 1*2 - 1*2 - 1*1 + 0*1 = -1.
		

Crossrefs

Cf. A002088, A065093, A068341, A112963, A112964, A112966, A112968.

Programs

Maple

with(numtheory); f:=n->add(phi(i)*mobius(n-i),i=1..n-1);

PARI

a(n)=sum(i=1,n-1,moebius(i)*eulerphi(n-i)) \\ Charles R Greathouse IV, Feb 21 2013

Extensions

Corrected by N. J. A. Sloane, Mar 01 2006