Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the 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