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LeastCommonMultiple{q+1: q prime, q < prime(n), q+1 divides prime(n)+1}.
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%I #10 Aug 14 2024 08:33:48

%S 1,1,3,4,12,1,6,4,24,6,8,1,42,4,24,18,60,1,4,72,1,40,84,90,14,6,8,108,

%T 1,114,32,132,6,140,30,152,1,4,168,6,180,14,96,1,18,40,4,224,228,1,18,

%U 240,1,252,6,264,270,136,1,6,4,294,308,312,1,6,4,1,348,14,6,360,8,1

%N LeastCommonMultiple{q+1: q prime, q < prime(n), q+1 divides prime(n)+1}.

%H Matthew House, <a href="/A084200/b084200.txt">Table of n, a(n) for n = 1..10000</a>

%o (Python)

%o from math import lcm

%o from sympy import sieve

%o def a(n):

%o pn = sieve[n]

%o return lcm(*[q+1 for q in sieve.primerange(2, pn) if (pn+1)%(q+1)==0])

%o print([a(n) for n in range(1, 100)]) # _Michael S. Branicky_, Aug 13 2024

%Y Cf. A084196, A082539, A084197.

%K nonn

%O 1,3

%A _Reinhard Zumkeller_, May 18 2003

%E Definition and terms corrected by _Matthew House_, Aug 13 2024