67509842400domain: NAppears in sequencesAmicable 5-tuples: (x1,...,x5) such that sigma(x1)=...=sigma(x5)=x1+...+x5. Groups of 5 subsequent terms list the five members in increasing size.at n=10A233553Amicable 5-tuples: (x1,...,x5) such that sigma(x1)=...=sigma(x5)=x1+...+x5, x1<x2<x3<x4<x5. Sequence gives x1 numbers.at n=2A273928