|
|
A374083
|
|
Vertical moments of inertia of a unit lozenge tiling of the hexagon with side lengths n (see references for exact configuration).
|
|
1
|
|
|
1, 18, 93, 296, 725, 1506, 2793, 4768, 7641, 11650, 17061, 24168, 33293, 44786, 59025, 76416, 97393, 122418, 151981, 186600, 226821, 273218, 326393, 386976, 455625, 533026, 619893, 716968, 825021, 944850, 1077281, 1223168, 1383393, 1558866, 1750525, 1959336
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
REFERENCES
|
J. Propp, Enumeration of matchings: problems and progress, pp. 255-291 in L. J. Billera et al., eds, New Perspectives in Algebraic Combinatorics, Cambridge, 1999 (see Problem 6, note a(2) is erroneous in this reference, cf. A071092).
|
|
LINKS
|
|
|
FORMULA
|
a(n) = (7*n^4 - n^2) / 6.
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|