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A226582
Smallest number of integer-sided squares needed to tile a 9 X n rectangle.
3
0, 9, 6, 3, 6, 6, 3, 6, 7, 1, 6, 7, 4, 7, 7, 4, 7, 8, 2, 7, 8, 5, 8, 8, 5, 8, 9, 3, 8, 9, 6, 9, 9, 6, 9, 10, 4, 9, 10, 7, 10, 10, 7, 10, 11, 5, 10, 11, 8, 11, 11, 8, 11, 12, 6, 11, 12, 9, 12, 12, 9, 12, 13, 7, 12, 13, 10, 13, 13, 10, 13, 14, 8, 13, 14, 11, 14
OFFSET
0,2
FORMULA
G.f.: x*(4*x^10-4*x^9-6*x^8+x^7+3*x^6-3*x^5+3*x^3-3*x^2-3*x+9) / (x^10-x^9-x+1).
a(n) = 1 + a(n-9) for n>10.
EXAMPLE
a(19) = 7:
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MAPLE
a:= n-> `if`(n=1, 9, iquo(n, 9, 'r')+[0, 5, 6, 3, 6, 6, 3, 6, 7][r+1]):
seq(a(n), n=0..100);
CROSSREFS
Row m=9 of A113881, A219158.
Sequence in context: A271172 A019683 A020759 * A276538 A243313 A259469
KEYWORD
nonn,easy
AUTHOR
Alois P. Heinz, Jun 12 2013
STATUS
approved