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A117297
Triangle read by rows generated from the Narayana transform.
0
1, 1, 1, 1, 2, 4, 1, 3, 11, 37, 1, 4, 21, 122, 621, 1, 5, 34, 273, 2302, 16526, 1, 6, 50, 508, 2763, 66482, 640207
OFFSET
1,5
COMMENTS
The operation used in generating the triangle is analogous to the binomial transform operation used in generating triangle A058127.
FORMULA
Let a(1) = 1, then n-th row is generated by performing the operation (M * V) on the (n-1)-th row and extracting the first n terms. M = the Narayana triangle of A001263 considered as a transform. V = the (n-1)-th row of the triangle as a Vector, V; followed by zeros: [a, b, c, 0, 0, 0, ...].
EXAMPLE
4th row = (1, 3, 11, 37), the first four terms of M * V = (1, 3, 11, 37, 101, 231, 463, ...); where M = the Narayana triangle as an infinitely lower triangular matrix and V = the Vector formed by row 3: [1, 2, 4, 0, 0, 0, ...].
First few rows of the triangle:
1;
1, 1;
1, 2, 4;
1, 3, 11, 37;
1, 4, 21, 122, 621;
1, 5, 34, 273, 2302, 16526;
...
CROSSREFS
Sequence in context: A258219 A036560 A308244 * A112973 A162303 A128570
KEYWORD
nonn,tabl
AUTHOR
Gary W. Adamson, Apr 23 2006
STATUS
approved