

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
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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 1k, 2k+1, 3k+2, and 4 does not divide k+3 is 7.
a(4) = 13 because the smallest k such that 1k, 2k+1, 3k+2, 4k+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



KEYWORD

nonn


AUTHOR



EXTENSIONS

a(5) corrected (0, not 181) by Jon Perry, Nov 05 2014


STATUS

approved



