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A249051
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The smallest integer > 1 of exactly n consecutive integers divisible respectively by the first n natural numbers (A000027), or 0 if no such number exists.
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1
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2, 3, 7, 13, 0, 61, 421, 841, 0, 2521, 0, 27721, 0, 0, 360361, 720721, 0, 12252241, 0, 0, 0, 232792561, 0, 5354228881, 0, 26771144401, 0, 80313433201, 0, 2329089562801, 72201776446801, 0, 0, 0, 0, 144403552893601, 0, 0, 0, 5342931457063201, 0
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OFFSET
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1,1
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COMMENTS
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For all n > 1 and a(n) # 0, a(n) == 1 (mod p#), where p# are the primorial numbers (A034386).
When a(n) is not 0, a(n) = A075059(n).
a(n) = 0 when n is a member of A080765.
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LINKS
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EXAMPLE
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a(3) = 7 because the smallest k such that 1|k, 2|k+1, 3|k+2, and 4 does not divide k+3 is 7.
a(4) = 13 because the smallest k such that 1|k, 2|k+1, 3|k+2, 4|k+3, and 5 does not divide k+4 is 13.
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MATHEMATICA
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f[n_] := Block[{lcm = LCM @@ Range@ n}, If[ lcm == LCM @@ Range[n + 1], 0, lcm + 1]]; Array[ f, 42] (* Robert G. Wilson v, Nov 13 2014 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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a(5) corrected (0, not 181) by Jon Perry, Nov 05 2014
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STATUS
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approved
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