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A127253
Product of number triangles A127243 and A127248.
1
1, 0, 1, -1, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, -1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1
OFFSET
0,1
COMMENTS
Rows containing -1 entries are indexed by twice the odious numbers given by A091855.
EXAMPLE
Triangle begins:
1;
0, 1;
-1, 0, 1;
0, 0, 0, 1;
0, 0, 0, 0, 1;
0, 0, 0, 0, 0, 1;
0, 0, 0, 0, 0, 0, 1;
0, 0, 0, 0, 0, 0, 0, 1;
0, 0, 0, 0, 0, 0, -1, 0, 1;
0, 0, 0, 0, 0, 0, 0, 0, 0, 1;
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1;
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1;
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1;
...
MATHEMATICA
T1[n_, k_] := SeriesCoefficient[(1 + ThueMorse[1 + k]*x)*x^k, {x, 0, n}]; (* A127243 *)
T2[n_, k_] := SeriesCoefficient[(1 - ThueMorse[1 + k]*x)*x^k, {x, 0, n}]; (* A127248 *)
T[n_, k_] := Sum[T2[n, j]*T1[j, k], {j, 0, n}];
Table[T[n, k], {n, 0, 12}, {k, 0, n}] // Flatten (* Amiram Eldar, Aug 04 2023 *)
CROSSREFS
Row sums are A127254.
Sequence in context: A086694 A357518 A093317 * A117944 A117945 A128937
KEYWORD
sign,tabl
AUTHOR
Paul Barry, Jan 10 2007
STATUS
approved