|
|
A121781
|
|
Series expansion for mean-squared radius of gyration of Ferrers diagrams on square lattice.
|
|
1
|
|
|
0, 8, 66, 366, 1640, 6404, 22696, 74832, 233312, 695680, 2000128, 5578752, 15166464, 40336384, 105256960, 270135296, 683188224, 1705443328, 4207935488, 10274078720, 24848105472, 59579301888, 141734445056
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
LINKS
|
|
|
FORMULA
|
Empirical (for n>=2): a(n) = 2^(n-7)*(50*n^3 + 3*n^2 + 70*n - 120 + 21*n^4)/3. - Vaclav Kotesovec, Nov 29 2012
Empirical G.f.: 5/16 - x/8 + (144*x^4 - 256*x^3 + 92*x^2 - 52*x + 5)/(16*(2*x-1)^5). - Vaclav Kotesovec, Nov 29 2012
|
|
MATHEMATICA
|
Rest[CoefficientList[Series[5/16-x/8+(144*x^4-256*x^3+92*x^2-52*x+5)/(16*(2*x-1)^5), {x, 0, 20}], x]] (* Vaclav Kotesovec, Nov 29 2012 *)
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|