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A305000
Number of labeled antichains of finite sets spanning some subset of {1,...,n} with singleton edges allowed.
23
1, 2, 8, 72, 1824, 220608, 498243968, 309072306743552, 14369391925598802012151296, 146629927766168786239127150948525247729660416
(list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
COMMENTS
Only the non-singleton edges are required to form an antichain.
Number of non-degenerate unate Boolean functions of n or fewer variables. - Aniruddha Biswas, May 11 2024
LINKS
Table of n, a(n) for n=0..9.
A. Biswas and P. Sarkar, Counting unate and balanced monotone Boolean functions, arXiv:2304.14069 [math.CO], 2023.
Gus Wiseman, Sequences enumerating clutters, antichains, hypertrees, and hyperforests, organized by labeling, spanning, and allowance of singletons.
FORMULA
Binomial transform of A304999.
Inverse binomial transform of A245079. - Aniruddha Biswas, May 11 2024
EXAMPLE
The a(2) = 8 antichains:
{}
{{1}}
{{2}}
{{1,2}}
{{1},{2}}
{{1},{1,2}}
{{2},{1,2}}
{{1},{2},{1,2}}
CROSSREFS
Cf. A006126, A261005, A304996, A304997, A304998, A304999, A305000, A305001.
Cf. A000372, A003182, A014466, A293606, A293993, A306505, A320449, A321679.
Cf. A245079.
Sequence in context: A125814 A295044 A374872 * A013002 A012998 A143760
Adjacent sequences: A304997 A304998 A304999 * A305001 A305002 A305003
KEYWORD
nonn,more
AUTHOR
Gus Wiseman, May 23 2018
EXTENSIONS
a(5)-a(8) from Gus Wiseman, May 31 2018
a(9) from Aniruddha Biswas, May 11 2024
STATUS
approved

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Last modified September 30 21:24 EDT 2024. Contains 376365 sequences.
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