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A089246 Triangular array read by rows: a(n, k) is the number of ordered m-tuples of positive integers (x_1, ..., x_m) such that max x_i = n+1-m and there are k ones (0 <= k <= n). 3
1, 0, 1, 1, 0, 1, 2, 2, 0, 1, 5, 5, 3, 0, 1, 14, 15, 9, 4, 0, 1, 43, 50, 31, 14, 5, 0, 1, 144, 180, 118, 54, 20, 6, 0, 1, 523, 695, 481, 229, 85, 27, 7, 0, 1, 2048, 2869, 2081, 1035, 395, 125, 35, 8, 0, 1, 8597, 12616, 9535, 4929, 1951, 629, 175, 44, 9, 0, 1, 38486, 58862 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,7

COMMENTS

The row sums are given by A047970 because row n counts the same tuples as the n-th antidiagonal of A047969.

LINKS

Table of n, a(n) for n=0..67.

EXAMPLE

a(5, 0) = 14: (5), (4,2), (2,4), (4,3), (3,4), (4,4),

(3,2,2), (2,3,2), (2,2,3), (3,3,2), (3,2,3), (2,3,3), (3,3,3), (2,2,2,2).

a(5, 1) = 15: (4,1), (1,4), (3,3,1), (3,1,3), (1,3,3), 6 permutations of (3,2,1) and 4 permutations of (2,2,2,1).

CROSSREFS

Cf. A047969, A047970, A089302.

Sequence in context: A188285 A273899 A102404 * A291684 A105929 A065600

Adjacent sequences:  A089243 A089244 A089245 * A089247 A089248 A089249

KEYWORD

nonn,tabl,easy

AUTHOR

Alford Arnold, Dec 22 2003

EXTENSIONS

Edited and extended by David Wasserman, Sep 07 2005

STATUS

approved

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Last modified May 20 20:16 EDT 2019. Contains 323426 sequences. (Running on oeis4.)