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A249051 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. 1
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 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
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.
LINKS
EXAMPLE
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.
MATHEMATICA
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 *)
CROSSREFS
Sequence in context: A084423 A361910 A068134 * A329413 A225093 A278007
KEYWORD
nonn
AUTHOR
Robert G. Wilson v, Oct 30 2014
EXTENSIONS
a(5) corrected (0, not 181) by Jon Perry, Nov 05 2014
Sequence corrected by Robert G. Wilson v, Nov 13 2014
STATUS
approved

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Last modified July 17 18:40 EDT 2024. Contains 374377 sequences. (Running on oeis4.)