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A211026
Number of segments needed to draw (on the infinite square grid) a diagram of regions and partitions of n.
3
4, 6, 8, 12, 16, 24, 32, 46, 62, 86, 114, 156, 204, 272, 354, 464, 596, 772, 982, 1256, 1586, 2006, 2512, 3152, 3918, 4874, 6022, 7438, 9132, 11210, 13686, 16700, 20288, 24622, 29768, 35956, 43276, 52032, 62372, 74678, 89168, 106350
OFFSET
1,1
COMMENTS
On the infinite square grid the diagram of regions of the set of partitions of n is represented by a rectangle with base = n and height = A000041(n). The rectangle contains n shells. Each shell contains regions. Each row of a region is a part. Each part of size k contains k cells. The number of regions equals the number of partitions of n (see illustrations in the links section). For a minimalist version see A139582. For the definition of "region of n" see A206437.
FORMULA
a(n) = 2*A000041(n) + 2 = 2*A052810(n) = A139582(n) + 2.
KEYWORD
nonn
AUTHOR
Omar E. Pol, Oct 29 2012
EXTENSIONS
a(18) corrected by Georg Fischer, Apr 11 2024
STATUS
approved