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A026397
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Sum{T(n-k,k)}, 0<=k<=[ n/2 ], where T is the array in A026386.
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0
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1, 2, 3, 6, 10, 17, 31, 53, 92, 163, 282, 492, 863, 1501, 2621, 4582, 7987, 13946, 24354, 42489, 74179, 129497, 226000, 394523, 688670, 1202020, 2098239, 3662553, 6392969, 11159290, 19478867, 34000750, 59349706, 103596641
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OFFSET
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0,2
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LINKS
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FORMULA
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G.f.: [(1+x)(1+x+x^2)]/[1-x^2-3x^3-x^4]. - Ralf Stephan, Apr 30 2004
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MATHEMATICA
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LinearRecurrence[{0, 1, 3, 1}, {1, 2, 3, 6}, 40] (* Harvey P. Dale, Apr 15 2015 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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