OFFSET
0,16
EXAMPLE
For n = 15, there are 6 ways to choose the four disjoint subsets:
15 = 7 + 8 = 4 + 5 + 6 = 1 + 2 + 3 + 9,
15 = 6 + 9 = 3 + 5 + 7 = 1 + 2 + 4 + 8,
15 = 6 + 9 = 3 + 4 + 8 = 1 + 2 + 5 + 7,
15 = 6 + 9 = 2 + 5 + 8 = 1 + 3 + 4 + 7,
15 = 7 + 8 = 2 + 4 + 9 = 1 + 3 + 5 + 6,
15 = 7 + 8 = 1 + 5 + 9 = 2 + 3 + 4 + 6, so a(15) = 6.
CROSSREFS
KEYWORD
nonn,nice
AUTHOR
Jean-Marc Rebert, Jun 07 2023
EXTENSIONS
More terms from David A. Corneth, Jun 08 2023
STATUS
approved