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%I #5 Feb 01 2017 13:44:41
%S 1,1,1,1,2,1,1,3,3,1,-1,4,6,4,1,-4,-5,10,10,5,1,-14,-24,-15,20,15,6,1,
%T -34,-98,-84,-35,35,21,7,1,69,-272,-392,-224,-70,56,28,8,1,496,621,
%U -1224,-1176,-504,-126,84,36,9,1,2896,4960,3105,-4080,-2940,-1008,-210,120,45,10,1
%N Triangle read by rows, e.g.f. exp(x*z)*(2*(exp(z)+1)/(cosh(z)+cos(z))-1).
%e Triangle starts:
%e [ 1]
%e [ 1, 1]
%e [ 1, 2, 1]
%e [ 1, 3, 3, 1]
%e [ -1, 4, 6, 4, 1]
%e [ -4, -5, 10, 10, 5, 1]
%e [ -14, -24, -15, 20, 15, 6, 1]
%e [ -34, -98, -84, -35, 35, 21, 7, 1]
%p A281587_row := proc(n) exp(x*z)*(2*(exp(z)+1)/(cosh(z)+cos(z))-1);
%p n!*coeff(series(%,z,n+1),z,n); PolynomialTools:-CoefficientList(%,x) end:
%p for n from 0 to 12 do A281587_row(n) od;
%Y Cf. A130595 (m=1), A109449 (m=2), A215064 (m=3), A281587 (m=4).
%Y Cf. A178964 (col. 0), A281588 (col. 1).
%K sign,tabl
%O 0,5
%A _Peter Luschny_, Feb 01 2017