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A318766
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a(0) = 1; for n > 0, a(n) = (prime(n)^2 - 1) * a(n-1).
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1
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1, 3, 24, 576, 27648, 3317760, 557383680, 160526499840, 57789539942400, 30512877089587200, 25630816755253248000, 24605584085043118080000, 33660439028338985533440000, 56549537567609495696179200000, 104503545424942348046539161600000
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OFFSET
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0,2
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COMMENTS
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LINKS
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FORMULA
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a(n) = A084920(n) * a(n-1) for n > 0.
a(n) = Product_{k=1..n} (prime(k)^2 - 1).
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MATHEMATICA
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a[n_]:=Product[Prime[k]^2-1, {k, 1, n}]; Join[{1}, Array[a, nmax]] (* Stefano Spezia, Sep 03 2018 *)
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PROG
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(PARI) {a(n) = prod(k=1, n, prime(k)^2-1)}
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CROSSREFS
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Product_{k=1..n} (prime(k)^m - 1): A005867 (m=1), this sequence (m=2).
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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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