OFFSET
0,3
COMMENTS
1 followed by period 60: (1, 13, ..., 90) repeated; offset 0.
LINKS
Alois P. Heinz, Table of n, a(n) for n = 0..1000
FORMULA
G.f.: see Maple program.
EXAMPLE
a(3) = 6, because there are 6 tilings of a 3 X 6 rectangle using integer-sided rectangular tiles of area 3:
._._._._._._. ._____._._._. ._._____._._.
| | | | | | | |_____| | | | | |_____| | |
| | | | | | | |_____| | | | | |_____| | |
|_|_|_|_|_|_| |_____|_|_|_| |_|_____|_|_|
._._._____._. ._._._._____. ._____._____.
| | |_____| | | | | |_____| |_____|_____|
| | |_____| | | | | |_____| |_____|_____|
|_|_|_____|_| |_|_|_|_____| |_____|_____|
MAPLE
gf:= -(89*x^16 +90*x^15 +103*x^14 +109*x^13 +144*x^12 +58*x^11 +103*x^10 +91*x^9 +120*x^8 +91*x^7 +103*x^6 +58*x^5 +56*x^4 +21*x^3 +15*x^2 +2*x +1) / (x^16 +x^15 +x^14 +x^13 +x^12 -x^4 -x^3 -x^2 -x -1):
a:= n-> coeff(series(gf, x, n+1), x, n):
seq(a(n), n=0..100);
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Alois P. Heinz, Dec 06 2012
STATUS
approved