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%I #7 Nov 06 2022 07:48:22
%S 1,2,1,2,2,1,3,2,2,1,4,1,1,2,4,3,2,1,2,6,1,4,2,3,7,1,2,6,1,1,8,2,1,2,
%T 5,2,1,2,2,1,6,1,8,1,3,10,2,4,2,1,3,4,11,6,1,2,3,4,1,1,2,7,2,2,1,1,2,
%U 13,2,5,1,6,4,1,2,8,1,1,1,1,2,1,12,1,2,2,15,1,1,4,6,4,2,2,10,6,1,3,2,1,2,3,2
%N Largest k such that k^2 divides prime(n)+1.
%C A160697 and A160698 give record values and where they occur.
%H Reinhard Zumkeller, <a href="/A160696/b160696.txt">Table of n, a(n) for n = 1..10000</a>
%F a(A049097(n)) = 1; a(A049098(n)) > 1;
%F a(n) = A000188(A008864(n)).
%o (PARI) a(n) = core(prime(n)+1, 1)[2]; \\ _Michel Marcus_, Nov 06 2022
%Y Cf. A000188, A008864, A049097, A049098.
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, May 24 2009