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A139486
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a(n) = Product_{j=0..n-1} (2^j + 2).
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1
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1, 3, 12, 72, 720, 12960, 440640, 29082240, 3780691200, 975418329600, 501365021414400, 514400511971174400, 1054521049540907520000, 4321427261018639016960000, 35409774976786728104970240000, 580224572769627326728042352640000
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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 >= 1, a(n) = 2^(n-1) * 3 * A028361(n-1).
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PROG
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(PARI) { a(n) = prod(j=0, n-1, 2^j+2) }
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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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EXTENSIONS
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STATUS
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approved
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