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A220130 Number of tilings of an n X 5 rectangle using integer-sided rectangular tiles of area n. 2
1, 1, 8, 4, 16, 2, 13, 1, 16, 4, 9, 1, 21, 1, 8, 5, 16, 1, 13, 1, 17, 4, 8, 1, 21, 2, 8, 4, 16, 1, 14, 1, 16, 4, 8, 2, 21, 1, 8, 4, 17, 1, 13, 1, 16, 5, 8, 1, 21, 1, 9, 4, 16, 1, 13, 2, 16, 4, 8, 1, 22, 1, 8, 4, 16, 2, 13, 1, 16, 4, 9, 1, 21, 1, 8, 5, 16, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

1 followed by period 60: (1, 8, ..., 22) 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) = 4, because there are 4 tilings of a 3 X 5 rectangle using integer-sided rectangular tiles of area 3:

._._._._._.   ._____._._.   ._._____._.   ._._._____.

| | | | | |   |_____| | |   | |_____| |   | | |_____|

| | | | | |   |_____| | |   | |_____| |   | | |_____|

|_|_|_|_|_|   |_____|_|_|   |_|_____|_|   |_|_|_____|

MAPLE

gf:= -(21*x^12 +22*x^11 +51*x^10 +56*x^9 +80*x^8 +65*x^7 +72*x^6 +45*x^5 +40*x^4 +16*x^3 +11*x^2 +2*x +1) / (x^12 +x^11 +2*x^10 +2*x^9 +2*x^8 +x^7 -x^5 -2*x^4 -2*x^3 -2*x^2 -x -1):

a:= n-> coeff(series(gf, x, n+1), x, n):

seq(a(n), n=0..100);

CROSSREFS

Row n=5 of A220122.

Sequence in context: A156279 A203072 A131873 * A276071 A040059 A178603

Adjacent sequences:  A220127 A220128 A220129 * A220131 A220132 A220133

KEYWORD

nonn,easy

AUTHOR

Alois P. Heinz, Dec 06 2012

STATUS

approved

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Last modified December 8 21:59 EST 2021. Contains 349596 sequences. (Running on oeis4.)