%I A107758
%S A107758 1,4,5,8,7,20,9,16,14,28,13,40,15,36,35,32,19,56,21,56
%N A107758 (+2)Sigma(n) : If n=Product p_i^r_i then (+2)Sigma(n)=Product (2+Sum 
               p_i^s_i, s_i=1 to r_i)=Product(1+(p_i^(r_i+1)-1)/(p_i-1)), (+2)Sigma(1)=1.
%e A107758 (+2)Sigma(6)=(2+2)*(2+3)=20.
%Y A107758 Cf. A107759, A052396.
%Y A107758 Sequence in context: A020804 A021222 A132023 this_sequence A104883 A154885 
               A042956
%Y A107758 Adjacent sequences: A107755 A107756 A107757 this_sequence A107759 A107760 
               A107761
%K A107758 nonn,mult
%O A107758 1,2
%A A107758 Yasutoshi Kohmoto (zbi74583(AT)boat.zero.ad.jp), May 25 2005