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A219861
Number of ways to dissect a nonsquare rectangle into n rectangles of equal area up to symmetry.
2
1, 2, 4, 11, 35, 130, 562, 2685, 13901, 76046
OFFSET
1,2
EXAMPLE
There are 4 ways (up to symmetry) to form a nonsquare rectangle from 3 rectangles with the same area:
+-----+ +-+-+-+ +-----+ +-+---+
| | | | | | | | | | |
+-----+ | | | | +--+--+ | | |
| | | | | | | | | | +---+
+-----+ | | | | | | | | | |
| | | | | | | | | | | |
+-----+ +-+-+-+ +--+--+ +-+---+
So a(3)=4.
The eleven solutions for n=4 can be seen as a subset of the illustration of A189243(4) = 21 in that entry. - N. J. A. Sloane, Dec 05 2012
CROSSREFS
Sequence in context: A186998 A243788 A245465 * A193058 A179379 A086611
KEYWORD
nonn,more
AUTHOR
Geoffrey H. Morley, Nov 29 2012
EXTENSIONS
a(7)-a(10) from Geoffrey H. Morley, Dec 16 2012
STATUS
approved