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A126885
T(n,k) = n*T(n,k-1) + k, with T(n,1) = 1, square array read by ascending antidiagonals (n >= 0, k >= 1).
2
1, 1, 2, 1, 3, 3, 1, 4, 6, 4, 1, 5, 11, 10, 5, 1, 6, 18, 26, 15, 6, 1, 7, 27, 58, 57, 21, 7, 1, 8, 38, 112, 179, 120, 28, 8, 1, 9, 51, 194, 453, 543, 247, 36, 9, 1, 10, 66, 310, 975, 1818, 1636, 502, 45, 10, 1, 11, 83, 466, 1865, 4881, 7279, 4916, 1013, 55, 11
OFFSET
0,3
FORMULA
T(1,k) = k*(k + 1)/2, and T(n,k) = (k - (k + 1)*n + n^(k + 1))/(n^2 - 2*n + 1) elsewhere.
T(n,k) = third entry in the vector M^k * (1, 0, 0), where M is the following 3 X 3 matrix:
1, 0, 0
1, 1, 0
1, 1, n.
EXAMPLE
Square array begins:
n\k | 1 2 3 4 5 6 7 8 ...
-------------------------------------------------
0 | 1 2 3 4 5 6 7 8 ... A000027
1 | 1 3 6 10 15 21 28 36 ... A000217
2 | 1 4 11 26 57 120 247 502 ... A000295
3 | 1 5 18 58 179 543 1636 4916 ... A000340
4 | 1 6 27 112 453 1818 7279 29124 ... A014825
5 | 1 7 38 194 975 4881 24412 122068 ... A014827
6 | 1 8 51 310 1865 11196 67183 403106 ... A014829
7 | 1 9 66 466 3267 22875 160132 1120932 ... A014830
8 | 1 10 83 668 5349 42798 342391 2739136 ... A014831
...
PROG
(Maxima)
T(n, k) := if k = 1 then 1 else n*T(n, k - 1) + k$
create_list(T(n - k + 1, k), n, 0, 20, k, 1, n + 1);
/* Franck Maminirina Ramaharo, Jan 26 2019 */
CROSSREFS
Antidiagonal sums: A134195. - Gary W. Adamson, Oct 12 2007
Sequence in context: A034356 A075195 A293311 * A239986 A285548 A130305
KEYWORD
nonn,easy,tabl
AUTHOR
Gary W. Adamson, Dec 30 2006
EXTENSIONS
Edited and name clarified by Franck Maminirina Ramaharo, Jan 26 2019
STATUS
approved