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A124789
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Expansion of (1+x^2)/(1-x^4-x^5).
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3
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1, 0, 1, 0, 1, 1, 1, 1, 1, 2, 2, 2, 2, 3, 4, 4, 4, 5, 7, 8, 8, 9, 12, 15, 16, 17, 21, 27, 31, 33, 38, 48, 58, 64, 71, 86, 106, 122, 135, 157, 192, 228, 257, 292, 349, 420, 485, 549, 641, 769, 905, 1034, 1190, 1410, 1674, 1939, 2224, 2600, 3084, 3613
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OFFSET
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0,10
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COMMENTS
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LINKS
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FORMULA
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a(n) = Sum_{k=0..floor(n/2)} C(floor(k/2),n-2*k).
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MATHEMATICA
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CoefficientList[Series[(1+x^2)/(1-x^4-x^5), {x, 0, 60}], x] (* or *) LinearRecurrence[ {0, 0, 0, 1, 1}, {1, 0, 1, 0, 1}, 60] (* Harvey P. Dale, Aug 20 2013 *)
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CROSSREFS
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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