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A218536
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1^2 * 3^2 * 5^2 * ... * (p-4)^2 * (p-2)^2 where p is the n-th prime number (n >= 2).
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0
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1, 9, 225, 893025, 108056025, 4108830350625, 1187451971330625, 21004837920867425625, 4132819745225119839515625, 3475701405734325785032640625, 454631398596176852476116706640625, 5601513462103494999358233942519140625, 9416144129795975093921191257374675390625
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OFFSET
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2,2
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COMMENTS
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a(n) is congruent to 1 or -1 (modulo the n-th prime).
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REFERENCES
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Kenneth Rosen, Elementary Number Theory and its Applications, Addison Wesley, page 223.
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LINKS
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EXAMPLE
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a(4)= 225 because the 4th prime number is 7 and 1^2*3^2*5^2 = 225. 225 is congruent to 1 (mod 7).
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MATHEMATICA
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Table[Product[(Prime[n] - 2i)^2, {i, n}], {n, 2, 15}]
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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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