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A115358
Inverse of matrix (1,x)+(x,x^2) (expressed in Riordan array notation).
2
1, -1, 1, 0, 0, 1, 1, -1, 0, 1, 0, 0, 0, 0, 1, 0, 0, -1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, -1, 1, 0, -1, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, -1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, -1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, -1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, -1, 0, 1
OFFSET
0,1
COMMENTS
Row sums are A035263 (first Feigenbaum symbolic (or period-doubling) sequence). Columns are signed stretched Fredholm-Rueppel sequences. Inverse is A115356.
FORMULA
Number triangle whose k-th column has g.f. x^k*sum{j>=0, (-1)^j*(x^(2j-1))^(k+1)}.
EXAMPLE
Triangle begins
1;
-1, 1;
0, 0, 1;
1, -1, 0, 1;
0, 0, 0, 0, 1;
0, 0, -1, 0, 0, 1;
0, 0, 0, 0, 0, 0, 1;
-1, 1, 0, -1, 0, 0, 0, 1;
0, 0, 0, 0, 0, 0, 0, 0, 1;
0, 0, 0, 0, -1, 0, 0, 0, 0, 1;
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1;
CROSSREFS
Sequence in context: A016410 A230412 A115361 * A325898 A117904 A259030
KEYWORD
easy,sign,tabl
AUTHOR
Paul Barry, Jan 21 2006
STATUS
approved