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%I #14 Oct 20 2022 07:43:59
%S 3,4,3,6,12,8,3,4,6,12,12,14,24,12,3,18,12,20,6,8,12,24,12,6,42,4,24,
%T 30,12,32,3,12,18,24,12,38,60,28,6,42,24,44,12,12,24,48,12,8,6,36,42,
%U 54,12,12,24,20,30,60,12,62,96,8,3,42,12,68,18,24,24,72,12,74,114,12,60,24,84,80,6,4,42,84,24,18,132,60,12,90,12,56,24,32,48,60,12,98,24,12,6
%N Least common multiple of the prime factors of n, each increased by 1.
%C If n is prime, then a(n) = n + 1. - _Wesley Ivan Hurt_, Apr 05 2014
%C If n is a composite squarefree number and a(n) divides n+1, then n is a Lucas-Carmichael number (A006972). - _Daniel Suteu_, Oct 02 2022
%H Daniel Suteu, <a href="/A238162/b238162.txt">Table of n, a(n) for n = 2..10000</a>
%e The prime factors of 6 are 2 and 3, which become 3 and 4 when respectively increased by 1, and lcm(3, 4) = 12. Therefore, a(6) = 12.
%o (PARI) a(n) = my(f=factor(n)); lcm(vector(#f~, k, f[k, 1]+1)); \\ _Daniel Suteu_, Oct 02 2022
%Y Cf. A006972.
%K nonn
%O 2,1
%A _Joseph L. Pe_, Feb 18 2014