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A190662
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Least semiprime having prime factors that differ by 2*n!.
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1
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15, 21, 85, 265, 2761, 10129, 111001, 887161, 21047881, 210471241, 1037836969, 68018232241, 361167207241, 3312775065961, 49691625984361, 1548286451713369, 16361621692416529, 294509190463488529
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OFFSET
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1,1
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LINKS
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EXAMPLE
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a(5) = 2761 because 2761 = 11 * 251 , and 251 - 11 = 240 = 2*120 = 2*5!
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MATHEMATICA
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f[n_] := Block[{p=3}, While[! PrimeQ[p+2*n!], p=NextPrime[p]]; p (p + 2*n!)]; Table[f[n], {n, 60}]
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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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