A166086 - OEIS

%I #3 Mar 31 2012 13:21:20

%S 1,1,3,1,5,1,17,1,5,1,11,1,13,1,5,5,15,1,29,1,13,1,9,1,32,5,17,1,15,1,

%T 37,11,5,17,15,1,90,1,17,1,27,1,29,9,17,1,37,1,15,1,39,50,19,1,37,13,

%U 25,1,25,1,161,19,5,1,17,1,53,1,84,5,41,1,29,11,5,1,45,1,62,3,51,1,19

%N Number of times Sum_{i=1..u} J(i,4n+3) obtains value zero when u ranges from 1 to (4n+3). Here J(i,k) is the Jacobi symbol.

%H A. Karttunen, <a href="/A166086/b166086.txt">Table of n, a(n) for n = 0..65536</a>

%Y a(n) = A166040(A005408(n)). Bisection of A166040. A165468 gives the positions of 1's, and respectively, A166052, A166054, A166056 and A166058 give the positions of 3's, 5's, 7's and 9's in this sequence. Note how 3's seem to be more rare than 5's, and 7's more rare than 9's.

%K nonn

%O 0,3

%A _Antti Karttunen_, Oct 08 2009