%I #9 Jul 18 2021 01:54:26

%S 52,156,780,1248,13260,19968,468480

%N Third element t of (-1)sigma sociable triple (r,s,t): s=(-1)sigma(r), t=(-1)sigma(s), r=(-1)sigma(t), where if x=Product p(i)^r(i), then (-1)sigma(x)=Product(-1+(Sum p(i)^s(i), s(i)=1 to r(i))).

%C Definition unclear, see comments in A049057. - _Sean A. Irvine_, Jul 17 2021

%e Factorizations 2^2*13, 2^2*3*13, 2^2*3*5*13, 2^5*3*13, 2^2*3*5*13*17, 2^9*3*13, 2^9*3*5*61

%Y Cf. A049057, A049058, A049060.

%K nonn

%O 0,1

%A _Yasutoshi Kohmoto_