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A057643 Least common multiple of all (k+1)'s, where the k's are the positive divisors of n.

%I A057643 #30 Jun 30 2022 12:47:15
%S A057643 2,6,4,30,6,84,8,90,20,66,12,5460,14,120,48,1530,18,7980,20,2310,88,
%T A057643 276,24,81900,78,378,140,3480,30,114576,32,16830,204,630,72,3838380,
%U A057643 38,780,280,284130,42,397320,44,4140,5520,1128,48,9746100,200,14586,468
%N A057643 Least common multiple of all (k+1)'s, where the k's are the positive divisors of n.
%C A057643 a(n) is a divisor of A020696(n). - _Ivan Neretin_, May 27 2015
%H A057643 Carl R. White, <a href="/A057643/b057643.txt">Table of n, a(n) for n = 1..10000</a>
%e A057643 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.
%p A057643 f:= n -> ilcm(op(map(`+`,numtheory:-divisors(n),1)));
%p A057643 seq(f(n),n=1..100); # _Robert Israel_, Jul 24 2014
%t A057643 a057643[n_Integer] := Apply[LCM, Map[# + 1 &, Divisors[n]]]; Table[a057643[n], {n, 10000}] (* _Michael De Vlieger_, Jul 19 2014 *)
%o A057643 (PARI) a(n)=lcm(apply(d->d+1,divisors(n))) \\ _Charles R Greathouse IV_, Feb 14 2013
%o A057643 (Python)
%o A057643 from math import lcm
%o A057643 from sympy import divisors
%o A057643 def A057643(n): return lcm(*(d+1 for d in divisors(n,generator=True))) # _Chai Wah Wu_, Jun 30 2022
%Y A057643 Cf. A119250.
%Y A057643 Cf. A020696 (product instead of LCM).
%K A057643 nonn
%O A057643 1,1
%A A057643 _Leroy Quet_, Oct 11 2000