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A121780
Series expansion for mean-squared radius of gyration of stack polygons on square lattice.
1
0, 8, 66, 444, 2541, 12840, 59113, 253600, 1029802, 4002112, 15005189, 54603436, 193743969, 672725072, 2292470170, 7685026612, 25392243845, 82826447752, 267077278409, 852322922488, 2694626921682, 8446754831544
OFFSET
1,2
FORMULA
Empirical g.f.: x^2*(8 - 54*x + 214*x^2 - 489*x^3 + 605*x^4 - 386*x^5 + 177*x^6 - 120*x^7 + 19*x^8 - x^9) / (1 - 3*x + x^2)^5. - Colin Barker, Apr 17 2017
CROSSREFS
Sequence in context: A121782 A212784 A121781 * A121779 A051825 A218927
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Aug 30 2006
STATUS
approved