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A226892
Number of squares of size n^2 in all tilings of an (n+2) X (n+2) square using integer-sided square tiles.
2
0, 29, 69, 153, 373, 917, 2321, 5933, 15317, 39737, 103461, 269925, 705169, 1843709, 4822949, 12620249, 33029909, 86456693, 226319505, 592468365, 1551031477, 4060538489, 10630442309, 27830559173, 72860864273, 190751433437, 499392464901, 1307424389913
OFFSET
0,2
LINKS
FORMULA
G.f.: (17*x^5 - 29*x^4 - 73*x^3 + 65*x^2 + 47*x - 29)*x / (-x^6 + 2*x^5 + 4*x^4 - 6*x^3 - 2*x^2 + 4*x - 1).
EXAMPLE
a(1) = 29:
._._._. ._._._. ._._._. ._._._. ._._._. ._._._.
| | | |_| |_|_|_| |_| | |_|_|_| |_|_|_|
| | |___|_| | |_| |_|___| |_| | |_|_|_|
|_____| |_|_|_| |___|_| |_|_|_| |_|___| |_|_|_|.
CROSSREFS
A diagonal of A226936.
Sequence in context: A163426 A344043 A165945 * A183194 A374613 A123372
KEYWORD
nonn
AUTHOR
Alois P. Heinz, Jun 22 2013
STATUS
approved