A124897 - OEIS

%I #10 Jul 26 2022 12:45:45

%S -1,-1,1,-1,1,-1,0,1,1,-1,1,1,-1,-1,1,-1,-1,0,1,-1,-1,1,-1,-1,1,-1,-1,

%T 1,1,1,-1,0,-1,1,1,-1,-1,0,1,-1,0,1,0,1,1,1,1,1,1,1,1,1,-1,-1,-1,-1,0,

%U 1,1,1,1,1,-1,1,1,-1,-1,0,1,0,1,-1,1,-1,-1,1,-1,1,1,1,-1,0,1,-1,1,1,-1,1,-1,-1,-1,1,0,-1,1,1,-1,-1,0,1,1,1,-1,1,-1,1

%N a(n) = mu(n^2 + 1), mu = A008683.

%H Amiram Eldar, <a href="/A124897/b124897.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = A008683(A002522(n)) = A124895(n,1);

%F a(n) = 0 iff A059592(n) > 1;

%t MoebiusMu[Range[107]^2+1] (* _T. D. Noe_, Nov 27 2006 *)

%o (PARI) a(n) = moebius(n^2+1); \\ _Michel Marcus_, Jul 26 2022

%Y Cf. A002522, A008683, A059592, A124895.

%K sign

%O 1,1

%A _Reinhard Zumkeller_, Nov 12 2006

%E Corrected by _T. D. Noe_, Nov 27 2006