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A109456
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Number of Boolean functions of n variables that are self-dual and regular.
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2
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0, 1, 1, 2, 3, 7, 21, 135, 2470, 319124, 1214554343
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,4
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COMMENTS
| Or, number of self-dual 2-monotonic Boolean functions of n or fewer variables.
Agrees with A001532 for n <= 8 but then diverges.
The value for n=10 was calculated with BDD techniques; all solutions are characterized by a binary decision diagram with 30011986 nodes.
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REFERENCES
| D. E. Knuth, The Art of Computer Programming, Vol. 4, Section 7.1.1 (in preparation).
S. Muroga, T. Tsuboi and C. R. Baugh, Enumeration of threshold functions of eight variables, IEEE Trans. Computers, 19 (1970), 818-825.
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CROSSREFS
| Sequence in context: A002863 A047693 A001532 * A155745 A067738 A053966
Adjacent sequences: A109453 A109454 A109455 * A109457 A109458 A109459
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KEYWORD
| nonn,hard,more
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AUTHOR
| D. E. Knuth, Aug 17 2005
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EXTENSIONS
| a(10) from Don Knuth (knuth-bug(AT)cs.stanford.edu), Feb 06 2008
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