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A192104
Number of distinct (unordered) pairs of partitions of an 11-element set that have Rand distance n.
1
1163085, 5835060, 21482340, 74471760, 222185304, 612903720, 1469224350, 3164268690, 5762811670, 9538994388, 13513772745, 18112131840, 20675910420, 23653643310, 22677991578, 22923998460, 19287053775, 17554312490, 13495597225, 11143736604, 8029798920, 6035010960, 4254456690, 2872892550, 1924619235, 1215058680, 789847190
OFFSET
1,1
COMMENTS
The Rand distance of a pair of set partitions is the number of unordered pairs {x; y} such that there is a block in one partition containing both x and y, but x and y are in different blocks in the other partition.
LINKS
F. Ruskey and J. Woodcock, The Rand and block distances of pairs of set partitions, Combinatorial algorithms, 287-299, Lecture Notes in Comput. Sci., 7056, Springer, Heidelberg, 2011.
CROSSREFS
Cf. A192100 for set sizes 2..7. A192098, A192102 and A192103 for set sizes 8..10.
Sequence in context: A084554 A339982 A234554 * A210181 A204307 A233664
KEYWORD
nonn,fini
AUTHOR
Frank Ruskey and Yuji Yamauchi (eugene.uti(AT)gmail.com), Aug 08 2011
STATUS
approved