A234944 Array read by antidiagonals: T(i,j) = number of different optimal difference triangle sets M(i,j).

1, 1, 1, 1, 3, 1, 1, 12, 2, 2, 1, 8, 9, 1, 4, 1, 21, 12, 4, 2, 5, 1, 720, 174, 6, 3, 2, 1, 1, 4079, 3132, 92, 1, 4, 1, 1, 1, 3040, 71930, 117

Offset

1,5

Comments

This array gives the number of different ways to choose the optimal difference triangle sets M(i,j) described in A234943.

Links

Table of n, a(n) for n=1..40.

J. B. Shearer, Difference Triangle Sets: Known optimal solutions.

J. B. Shearer, Difference Triangle Sets: Discoverers

Example

Array begins:
j\i| 1,  2,  3,   4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15,
-----------------------------------------------------------------
1  | 1,   1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,  1,   1,   1 (A000012)
2  | 1,   3,   12,   8,  21, 720, 4079, 3040, 20505, 1669221, 14708525, 10567748,  (A234947)
3  | 1,   2,    9,  12, 174, 3132, 71930,   (A234945)
4  | 2,   1,    4,   6,  92, 117,   (A234946)
5  | 4,   2,    3,   1,
6  | 5,   2,    4,   4,
7  | 1,   1,    1,
8  | 1,   2,
9  | 1,   1,
10 | 2,
11 | 1
12 | 1
13 | 1
14 | 1
15 | 1
The entries match those in A234943.

Crossrefs

Rows give A234947, A234945, A234946.

Cf. A234943.

Sequence in context: A176421 A168552 A111473 * A067402 A113340 A134523

Adjacent sequences: A234941 A234942 A234943 * A234945 A234946 A234947

Keyword

nonn,tabl,more

Author

N. J. A. Sloane, Jan 08 2014

Status

approved