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A060381
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a(n) = prime(n)*prime(n+1)*...*prime(2*n-1), where prime(i) is the i-th prime.
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3
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1, 2, 15, 385, 17017, 1062347, 86822723, 10131543907, 1204461778591, 198229051666003, 35224440615606707, 6295457783127226289, 1331590860773071702483, 310692537866322378582047, 78832548083496383033878901, 21381953681344611984282084241
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OFFSET
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0,2
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COMMENTS
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For n >= 0, a(n+1) is the n-th power of 15 in the monoid defined by A306697. - Peter Munn, Feb 18 2020
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LINKS
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FORMULA
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(End)
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EXAMPLE
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a(1)=2; a(2) = 3*5 = 15; a(3) = 5*7*11 = 385.
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MAPLE
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seq(mul(ithprime(n+k), k=0..n-1), n=0..15); # Muniru A Asiru, Mar 16 2019
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MATHEMATICA
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Table[Times@@Prime[Range[n, 2n-1]], {n, 20}] (* Harvey P. Dale, Jul 19 2018 *)
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PROG
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(Haskell)
(GAP) P:=Filtered([1..200], IsPrime);;
a:=List([1..15], n->Product([0..n-1], k->P[n+k])); # Muniru A Asiru, Mar 16 2019
(PARI) a(n) = prod(k=n, 2*n-1, prime(k)); \\ Michel Marcus, Mar 16 2019
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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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