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A118245
Triangle generated from A001263 considered as a transform.
0
1, 1, 1, 1, 2, 1, 1, 4, 4, 1, 1, 7, 11, 7, 1, 11, 25, 25, 11, 1, 1, 16, 51, 74, 51, 16, 1, 1, 22, 96, 191, 191, 96, 22, 1, 1, 29, 169, 441, 602, 441, 169, 29, 1
OFFSET
1,5
COMMENTS
Each row of the triangle is a palindrome.
FORMULA
Let M be the Narayana (or Catalan) triangle, A001263 as an infinite lower triangular matrix. Generate an array by rows, taking the product (M * V); where V = rows of the Narayana triangle considered as vectors. Rows of the triangle are antidiagonals of the array.
EXAMPLE
First few rows of the array:
1, 1, 1, 1, 1, ...
1, 2, 4, 7, 11, ...
1, 4, 11, 25, 51, ...
1, 7, 25, 74, 191, ...
1, 11, 51, 191, 602, ...
...
n-th row of the array is generated from (M * V), where V in turn = n-th row of the Narayana triangle: (1); (1, 1); (1, 3, 1); (1, 6, 6, 1); ... i.e., terms followed by zeros to form a vector, as (1, 3, 1, 0, 0, 0, ...). Example: T(6,3) and T(6,4) = 25 = 1*0 + 1*1 + 6*1 + 6*18 = 0+1+6+18 = 25.
First few rows of the triangle:
1;
1, 1;
1, 2, 1;
1, 4, 4, 1;
1, 7, 11, 7, 1;
1, 11, 25, 25, 11, 1;
1, 16, 51, 74, 51, 16, 1;
1, 22, 96, 191, 191, 96, 22, 1;
...
CROSSREFS
Cf. A001263.
Sequence in context: A113582 A347147 A295213 * A104382 A086629 A203948
KEYWORD
nonn,tabl
AUTHOR
Gary W. Adamson, Apr 17 2006
STATUS
approved