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A239784
Number of pairs of functions (f,g) from a set of n elements into itself satisfying f(g(g(x))) = f(g(f(x))).
0
1, 1, 14, 351, 14776, 902605, 75313056, 8194699387
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OFFSET
0,3
LINKS
Table of n, a(n) for n=0..7.
CROSSREFS
Cf.
A181162
.
Sequence in context:
A020143
A161927
A253457
*
A113673
A184268
A223383
Adjacent sequences:
A239781
A239782
A239783
*
A239785
A239786
A239787
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 February 23 07:33 EST 2024. Contains 370269 sequences. (Running on oeis4.)