A049058 Second element s 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))).

60, 120, 480, 1464, 7680, 24504, 490080

Offset

0,1

Comments

Definition unclear, see comments in A049057. - Sean A. Irvine, Jul 17 2021

Links

Table of n, a(n) for n=0..6.

Example

Factorizations 2^2*3*5, 2^3*3*5, 2^5*3*5, 2^3*3*61, 2^9*3*5, 2^3*3*1021, 2^5*3*5*1021

Crossrefs

Cf. A049057, A049059, A049060.

Sequence in context: A252953 A309315 A275339 * A056501 A056491 A044247

Adjacent sequences: A049055 A049056 A049057 * A049059 A049060 A049061

Keyword

nonn

Author

Yasutoshi Kohmoto

Status

approved