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A057643
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Least common multiple of all (k+1)'s, where the k's are the positive divisors of n.
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8
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2, 6, 4, 30, 6, 84, 8, 90, 20, 66, 12, 5460, 14, 120, 48, 1530, 18, 7980, 20, 2310, 88, 276, 24, 81900, 78, 378, 140, 3480, 30, 114576, 32, 16830, 204, 630, 72, 3838380, 38, 780, 280, 284130, 42, 397320, 44, 4140, 5520, 1128, 48, 9746100, 200, 14586, 468
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OFFSET
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1,1
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COMMENTS
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LINKS
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EXAMPLE
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Since the positive divisors of 6 are 1, 2, 3 and 6, a(6) = LCM(1+1,2+1,3+1,6+1) = LCM(2,3,4,7) = 84.
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MAPLE
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f:= n -> ilcm(op(map(`+`, numtheory:-divisors(n), 1)));
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MATHEMATICA
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a057643[n_Integer] := Apply[LCM, Map[# + 1 &, Divisors[n]]]; Table[a057643[n], {n, 10000}] (* Michael De Vlieger, Jul 19 2014 *)
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PROG
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(Python)
from math import lcm
from sympy import divisors
def A057643(n): return lcm(*(d+1 for d in divisors(n, generator=True))) # Chai Wah Wu, Jun 30 2022
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CROSSREFS
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Cf. A020696 (product instead of LCM).
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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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