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EXAMPLE
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1;
1, 1, -1;
1, 5, -2, -2, 1;
1, 15, 13, -19, 3, 3, -1;
1, 37, 128, -26, -74, 46, -4, -4, 1;
1, 83, 679, 755, -654, -68, 230, -90, 5, 5, -1;
1, 177, 2866, 9048, 2091, -5741, 1856, 498, -545, 155, -6, -6, 1; ...
in which the o.g.f. of row n, R(x,n), is given by:
R(x,n) = (1-x)^(2*n-1) * Sum_{k>=0} k^n *(k+1)^(k-1) * exp(-(k+1)*x) * x^k/k!;
note that the coefficient of x^n in R(x,n), for n>=1, forms this sequence.
The signs of the terms of this sequence begin:
+,+,
-,-,-,-,
+,+,+,+,+,
-,-,-,-,-,-,-,
+,+,+,+,+,+,+,+,+,+,
-,-,-,-,-,-,-,-,-,-,-,
+,+,+,+,+,+,+,+,+,+,+,+,+,
-,-,-,-,-,-,-,-,-,-,-,-,-,-,
+,+,+,+,+,+,+,+,+,+,+,+,+,+,+,+,
-,-,-,-,-,-,-,-,-,-,-,-,-,-,-,-,-,
+,+,+,+,+,+,+,+,+,+,+,+,+,+,+,+,+,+,
-,-,-,-,-,-,-,-,-,-,-,-,-,-,-,-,-,-,-,
+,+,+,+,+,+,+,+,+,+,+,+,+,+,+,+,+,+,+,+,+, ...
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