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A271266
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a(n) = Product_{k=1..n} (k^2 + 21).
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0
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1, 22, 550, 16500, 610500, 28083000, 1600731000, 112051170000, 9524349450000, 971483643900000, 117549520911900000, 16692031969489800000, 2754185274965817000000, 523295202243505230000000, 113555058886840634910000000, 27934544486162796187860000000, 7737868822667094544037220000000
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OFFSET
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0,2
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COMMENTS
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Yin et al. prove that a(n) is never a square for n > 0.
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LINKS
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MATHEMATICA
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PROG
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(PARI) a(n) = prod(k=1, n, (k^2+21));
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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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