%I A117435
%S A117435 1,0,1,4,0,1,0,12,0,1,16,0,24,0,1,0,80,0,40,0,1,64,0,240,0,60,0,1,0,448,
%T A117435 0,560,0,84,0,1,256,0,1792,0,1120,0,112,0,1,0,2304,0,5376,0,2016,0,144,
%U A117435 0,1,1024,0,11520,0,13440,0,3360,0,180,0,1
%V A117435 1,0,1,-4,0,1,0,-12,0,1,16,0,-24,0,1,0,80,0,-40,0,1,-64,0,240,0,-60,0,
               1,0,-448,0,560,0,
%W A117435 -84,0,1,256,0,-1792,0,1120,0,-112,0,1,0,2304,0,-5376,0,2016,0,-144,0,
               1,-1024,0,11520,
%X A117435 0,-13440,0,3360,0,-180,0,1
%N A117435 Triangle related to exp(x)cos(2x).
%C A117435 Row sums are A006495 (with e.g.f. exp(x)cos(2x)). Inverse is A117436. 
               Diagonal sums are (1,0,-3,0,5,0,-7,...). Diagonals correspond to 
               rows of A117438.
%F A117435 Number triangle whose k-th column has e.g.f. (x^k/k!)*cos(2x); T(n,k)=C(n,
               k)*(-4)^((n-k)/2)*(1+(-1)^(n-k))/2.
%e A117435 Triangle begins
%e A117435 1,
%e A117435 0, 1,
%e A117435 -4, 0, 1,
%e A117435 0, -12, 0, 1,
%e A117435 16, 0, -24, 0, 1,
%e A117435 0, 80, 0, -40, 0, 1,
%e A117435 -64, 0, 240, 0, -60, 0, 1
%Y A117435 Cf. A117411.
%Y A117435 Sequence in context: A147312 A019974 A046781 this_sequence A117436 A166318 
               A166317
%Y A117435 Adjacent sequences: A117432 A117433 A117434 this_sequence A117436 A117437 
               A117438
%K A117435 easy,sign,tabl
%O A117435 0,4
%A A117435 Paul Barry (pbarry(AT)wit.ie), Mar 16 2006