%I A108086
%S A108086 1,1,1,1,2,1,1,3,3,1,1,4,6,4,1,1,5,10,10,5,1,1,6,15,20,15,6,1,1,7,21,35,
%T A108086 35,21,7,1,1,8,28,56,70,56,28,8,1,1,9,36,84,126,126,84,36,9,1,1,10,45,
%U A108086 120,210,252,210,120,45,10,1,1,11,55,165,330,462,462,330,165,55,11,1
%V A108086 1,-1,1,-1,-2,1,1,-3,-3,1,1,4,-6,-4,1,-1,5,10,-10,-5,1,-1,-6,15,20,-15,
               -6,1,1,-7,-21,
%W A108086 35,35,-21,-7,1,1,8,-28,-56,70,56,-28,-8,1,-1,9,36,-84,-126,126,84,-36,
               -9,1,-1,-10,45,
%X A108086 120,-210,-252,210,120,-45,-10,1,1,-11,-55,165,330,-462,-462,330,165,-55,
               -11,1
%N A108086 Triangle, read by rows, where T(0,0) = 1, T(n,k) = (-1)^(n+k)*T(n-1,k) 
               + T(n-1,k-1); a signed version of Pascal's triangle.
%C A108086 Row sums are 1,0,-2,-4,-4,0,8,16,16,0,-32,-64,-64,0,128,256,256,... Antidiagonal 
               sums are 1,-1,0,-1,-1,0,-1,1,0,1,1,0,1,-1,0,-1,-1,0,-1,1,0,1...
%F A108086 a(n, k) = (-1)^(int((n-k+1)/2)*A007318(n, k) (A007318 is Pascal's triangle).
%Y A108086 Cf. A007318, A009116, A090132.
%Y A108086 Sequence in context: A117440 A118433 A007318 this_sequence A130595 A108363 
               A076831
%Y A108086 Adjacent sequences: A108083 A108084 A108085 this_sequence A108087 A108088 
               A108089
%K A108086 sign,tabl
%O A108086 0,5
%A A108086 Gerald McGarvey (gerald.mcgarvey(AT)comcast.net), Jun 05 2005