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A239758
Number of pairs of functions (f,g) on a set of n elements into itself satisfying f(g(f(x))) = g(f(g(x))).
0
1, 1, 8, 147, 4672, 221245, 14695656, 1297497103
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OFFSET
0,3
LINKS
Table of n, a(n) for n=0..7.
CROSSREFS
Cf.
A000248
,
A000949
.
Sequence in context:
A064331
A230938
A351922
*
A239759
A279127
A259991
Adjacent sequences:
A239755
A239756
A239757
*
A239759
A239760
A239761
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 March 29 02:23 EDT 2024. Contains 371264 sequences. (Running on oeis4.)