Hi,Seqfans I computed two terms of the following generalized Amicable Number. Unitarysigma(x)=UnitarySigma(y)=3/10*((SquareRoot(x)+SquareRoot(y))^2-GCD(x,y)) x=5^3*2^2*3^2 y=5^3*7^2 x=5^2*17*2^4*3^2 y=5^2*17*13^2 Could anyone compute more term? Yasutoshi