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A239765
Number of pairs of functions (f,g) from a set of n elements into itself satisfying f(f(g(x))) = g(g(g(x))).
0
1, 1, 10, 189, 6304, 315065, 21848976, 1992930037
(list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
LINKS
Table of n, a(n) for n=0..7.
CROSSREFS
Cf. A181162.
Sequence in context: A121973 A223146 A365175 * A006409 A173813 A249643
Adjacent sequences: A239762 A239763 A239764 * A239766 A239767 A239768
KEYWORD
nonn,more
AUTHOR
Chad Brewbaker, Mar 26 2014
EXTENSIONS
a(6)-a(7) from Giovanni Resta, Mar 28 2014
STATUS
approved

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Last modified October 21 11:02 EDT 2024. Contains 376980 sequences.
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