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A109221
A number triangle related to the Fibonacci polynomials.
2
1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 5, 3, 1, 1, 1, 7, 5, 6, 1, 1, 1, 9, 7, 15, 6, 1, 1, 1, 11, 9, 28, 15, 10, 1, 1, 1, 13, 11, 45, 28, 35, 10, 1, 1, 1, 15, 13, 66, 45, 84, 35, 15, 1, 1, 1, 17, 15, 91, 66, 165, 84, 70, 15, 1, 1, 1, 19, 17, 120, 91, 286, 165, 210, 70, 21, 1, 1, 1, 21, 19
OFFSET
0,9
COMMENTS
The repeated columns are made up by taking every second element of columns in A011973. Row sums are A109222.
FORMULA
Number triangle T(n, k)=binomial(floor((2n-k)/2)+n-k, 2n-2k)
EXAMPLE
Rows begin
1;
1,1;
1,1,1;
1,1,3,1;
1,1,5,3,1;
1,1,7,5,6,1;
CROSSREFS
Sequence in context: A081060 A255811 A131268 * A369227 A360908 A351347
KEYWORD
easy,nonn,tabl
AUTHOR
Paul Barry, Jun 22 2005
STATUS
approved