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A164976
Triangle read by rows, expansion of 1/(1-2*y*x-x+x^2-y*x^2).
2
1, 1, 2, 0, 5, 4, -1, 4, 16, 8, -1, -3, 25, 44, 16, 0, -10, 7, 102, 112, 32, 1, -8, -41, 97, 344, 272, 64, 1, 4, -74, -80, 528, 1040, 640, 128, 0, 15, -33, -366, 121, 2168, 2928, 1472, 256, -1, 12, 75, -426, -1219, 1898, 7664, 7840, 3328, 512
OFFSET
0,3
COMMENTS
Leftmost column is A010892.
Rows sum up to A000244 and diagonals to A000073.
A164975 has a similar g.f.: x/(1-2*y*x-x-x^2+y*x^2).. - Georg Fischer, Oct 15 2023
LINKS
EXAMPLE
Triangle begins:
1;
1, 2;
0, 5, 4;
-1, 4, 16, 8;
-1, -3, 25, 44, 16;
0, -10, 7, 102, 112, 32;
1, -8, -41, 97, 344, 272, 64;
...
MAPLE
s := 1/(1-2*y*x-x+x^2-y*x^2): t := series(s, x, 12):
seq(print(seq(coeff(coeff(t, x, n), y, m), m=0..n)), n=0..11); # Georg Fischer, Oct 15 2023
CROSSREFS
Cf. A010892 (1st column), A000079 (right diagonal).
Sequence in context: A173732 A086280 A349950 * A261745 A083714 A215481
KEYWORD
tabl,sign
AUTHOR
Mark Dols, Sep 03 2009
EXTENSIONS
Missing commas inserted in what used to be the term "1-8-41" (now "1,-8,-41") by Geoff Bailey (geoff(AT)maths.usyd.edu.au), Nov 30 2009
Definition changed by Georg Fischer, Oct 15 2023
STATUS
approved