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A083268
a(n) is the lcm of related numbers to n (counted in A073757): related = {divisor-set, RRS}.
3
1, 2, 6, 12, 60, 30, 420, 840, 2520, 630, 27720, 4620, 360360, 90090, 120120, 720720, 12252240, 1531530, 232792560, 58198140, 77597520, 29099070, 5354228880, 892371480, 26771144400, 3346393050, 80313433200, 20078358300, 2329089562800
OFFSET
1,2
LINKS
FORMULA
a(n) = lcm(n, A038610(n)).
EXAMPLE
For n = 10: related terms = {1,2,5,10,3,7,9}; lcm(10,1,3,7,9) = 630 = a(10).
MATHEMATICA
a[n_] := LCM @@ Join[{n}, Select[Range[n], CoprimeQ[n, #] &]]; Array[a, 30] (* Amiram Eldar, Jun 20 2024 *)
PROG
(PARI) a(n)=my(t=lcm([1..n])/n, g); while((g=gcd(t, n))>1, t/=g); t*n \\ Charles R Greathouse IV, Nov 14 2014
CROSSREFS
Cf. A073757 (count), A083266 (sum), A083268 (LCM), A083267 (product), A038610.
Sequence in context: A117481 A343277 A341617 * A368901 A225628 A284650
KEYWORD
nonn
AUTHOR
Labos Elemer, May 13 2003
STATUS
approved