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Search: id:A034999
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| A034999 |
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Number of ways to cut a 2 x n rectangle into rectangles with integer sides. |
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+0
2
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| 2, 8, 34, 148, 650, 2864, 12634, 55756, 246098, 1086296, 4795090, 21166468, 93433178, 412433792, 1820570506, 8036386492, 35474325410, 156591247016, 691227204226, 3051224496244, 13468756547882, 59453967813584
(list; graph; listen)
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OFFSET
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1,1
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FORMULA
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a(n)=1+3^(n-1)+sum_{i=1}^{n-1} (1+3^(i-1))a(n-i)
a(n) = 6a(n - 1) - 7a(n - 2), a(n) = ((4 + sqrt(2)) (3 + sqrt(2))^n + (4 - sqrt(2)) (3 - sqrt(2))^n)/14 - N. Sato (nsato7(AT)yahoo.ca), May 10 2006
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EXAMPLE
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For a 2 X 2 rectangle we have: 11 11 12 11 12 21 23 12 11 22 12 23 13 31 11 23
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CROSSREFS
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Adjacent sequences: A034996 A034997 A034998 this_sequence A035000 A035001 A035002
Sequence in context: A117616 A014445 A113440 this_sequence A067336 A026387 A085362
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KEYWORD
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nonn
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AUTHOR
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Erich Friedman (erich.friedman(AT)stetson.edu)
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