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A183020
Largest members of k-sociable cycles of order r, with k > 1 and r > 1.
3
8132064, 14246719968, 97998179400, 582340505600
OFFSET
1,1
COMMENTS
A k-sociable (or multisociable) cycle of order r consists of r distinct positive integers such that the sum of the aliquot divisors (or proper divisors) of each is equal to k times the next term in the cycle, where k (the multiplicity) is a fixed positive integer.
In this sequence, a(1), a(2) and a(4) are the largest terms of 2-sociable cycles of order 3 (or bicrowds), and a(3) is the larger term of a 3-sociable cycle of order 2 (or triamicable pair).
No other terms <= 10^12.
CROSSREFS
KEYWORD
nonn,more
AUTHOR
STATUS
approved