%I A071934
%S A071934 1,0,1,2,3,4,5,6,7,6,7,8,9,10,11,12,13,12,13,14,15,16,17,18,19,18,19,
%T A071934 20,21,22,23,24,25,24,25,26,27,28,29,30,31,30,31,32,33,34,35,36,37,36,
%U A071934 37,38,39,40,41,42,43,42,43,44,45,46,47,48,49,48,49,50,51,52,53,54,55
%N A071934 a(n) = sum(i=1,n,K(i+1,i)) where K(x,y) is the Kronecker symbol (x/y).
%F A071934 a(n) = n - 2* ceil(n/8) + 2 if n == 1 (mod 8) a(n) = n - 2* ceil(n/8) 
               otherwise
%e A071934 Because 53-1 = 52 is not congruent to 1 (mod 8); a(71) = 71 -2*ceil(71/
               8) = 71 - 2*9 = 71-18 = 53
%o A071934 (PARI) for(n=1,100,print1(sum(i=1,n,kronecker(i+1,i)),","))
%Y A071934 Sequence in context: A161209 A000026 A005599 this_sequence A161658 A066853 
               A141258
%Y A071934 Adjacent sequences: A071931 A071932 A071933 this_sequence A071935 A071936 
               A071937
%K A071934 easy,nonn
%O A071934 1,4
%A A071934 Benoit Cloitre (benoit7848c(AT)orange.fr), Jun 14 2002