%I #12 Feb 12 2014 03:17:05
%S 1,-1,1,-1,-2,1,-1,-3,-3,1,-1,-4,-6,-4,1,-1,-5,-10,-10,-5,1,-1,-6,-15,
%T -20,-15,-6,1,-1,-7,-21,-35,-35,-21,-7,1,-1,-8,-28,-56,-70,-56,-28,-8,
%U 1
%N Signed version of Pascal's triangle. Diagonal positive, rest negative.
%C Matrix inverse of this lower triangular array is A154921. Signs in columns as in sequence A153881.
%C Exponential Riordan array [2-exp(x),x]. - _Paul Barry_, Apr 06 2011
%e From _Mats Granvik_, Jul 24 2009: (Start)
%e Table begins:
%e .1
%e -1....1
%e -1...-2....1
%e -1...-3...-3....1
%e -1...-4...-6...-4....1
%e -1...-5..-10..-10...-5....1
%e -1...-6..-15..-20..-15...-6....1
%e -1...-7..-21..-35..-35..-21...-7....1
%e -1...-8..-28..-56..-70..-56..-28...-8....1
%e -1...-9..-36..-84.-126.-126..-84..-36...-9....1
%e -1..-10..-45.-120.-210.-252.-210.-120..-45..-10....1
%e -1..-11..-55.-165.-330.-462.-462.-330.-165..-55..-11....1
%e (End)
%Y Cf. A007318, A153881.
%K sign,tabl
%O 1,5
%A _Mats Granvik_, Jan 17 2009