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A027107
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a(n) = Sum_{k=0..2n} (k+1) * A027082(n, 2n-k).
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5
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1, 6, 20, 62, 188, 566, 1700, 5102, 15308, 45926, 137780, 413342, 1240028, 3720086, 11160260, 33480782, 100442348, 301327046, 903981140, 2711943422, 8135830268, 24407490806, 73222472420, 219667417262, 659002251788
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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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For n>0, a(n) = 7*3^(n-1) - 1.
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MATHEMATICA
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PROG
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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