A192098 Number of distinct (unordered) pairs of partitions of an 8-element set that have Rand distance n.

5684, 23772, 69272, 183960, 391356, 696178, 941088, 1182888, 1150520, 1165416, 815640, 780570, 413840, 369180, 178080, 115780, 43512, 20734, 6860, 7098, 3508, 574, 840, 665, 476, 210, 28, 1

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

Table of n, a(n) for n=1..28.

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.

Sequence in context: A224683 A222824 A183638 * A287239 A204532 A269297

Adjacent sequences: A192095 A192096 A192097 * A192099 A192100 A192101

Keyword

nonn,fini,full

Author

Frank Ruskey and Yuji Yamauchi (eugene.uti(AT)gmail.com), Jul 21 2011

Status

approved