OFFSET
2,2
EXAMPLE
a(3) = 2 since when U(3) = {1,2} acts naturally on the three 2-subsets {0,1}, {0,2}, {1,2} of Z/(3) the orbits are {{0,1},{0,2}} and {{1,2}}. Note that 2{0,1} = {0,2} but there is no unit a in U(3) such that a{0,1} = {1,2}.
CROSSREFS
KEYWORD
nonn
AUTHOR
W. Edwin Clark, Jul 15 2001
EXTENSIONS
More terms from Sean A. Irvine, Apr 22 2023
STATUS
approved