A143987 Eigentriangle of (A007318)^(-1); row sums = A014182, exp(1-x-exp(-x)).
1, -1, 1, 1, 2, 0, -1, 3, 0, -1, 1, -4, 0, 4, 1, -1, 5, 0, -10, -5, 2, 1, -6, 0, 20, 15, -12, -9, -1, 7, 0, -35, -35, 42, 63, 9, 1, -8, 0, 56, 70, -112, -252, -72, 50, -1, 9, 0, -84, -126, 252, 756, 324, -450, -267, 1, -10, 0, 120, 210, -504, -1890, -1080, 2250, 2670, 413
Offset: 0
Examples
First few rows of the triangle = 1; -1, 1; 1, -2, 0; -1, 3, 0, -1; 1, -4, 0, 4, 1; -1, 5, 0, -10, -5, 2; 1, -6, 0, 20, 15, -12, -9; -1, 7, 0, -35, -35, 42, 63, 9; 1, -8, 0, 56, 70, -112, -252, 72, 50; ... Example: row 4 = (1, -4, 0, 4, 1) = termwise products of (1, -4, 6, -4, 1) and (1, 1, 0, -1, 1).= (1*1, -4*1, 6*0, -4*-1, 1*1).
Formula
A007318^(-1) = the inverse of Pascal's triangle.
Given A014182: (1, 0, -1, 1, 2, -9, 9,...) = expansion of exp(1-x-exp(-x)), we preface A014182 with a "1" getting (1, 1, 0, -1, 1, 2, -9,...).
Then diagonalize it as an infinite lower triangular matrix R =
1;
0, 1;
0, 0, 0;
0, 0, 0, -1;
0, 0, 0, 0, 1;
...
Finally, take the inverse binomial transform of triangle R, getting A143987.
Given the inverse of Pascal's triangle by rows, we apply termwise products of equal numbers of terms in the sequence: (1, 1, 0, -1, 1, 2, -9, 9,...).
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