A293452 Triangle T(n,k) read by rows: T(n,k) is the number of iterations to reach a final state for an n X k lattice of sandpiles on a torus according to rules specified in A249872.

0, 1, 7, 2, 14, 28, 7, 35, 65, 133, 10, 47, 86, 198, 316, 22, 86, 134, 331, 487, 913, 28, 106, 164, 399, 696, 1099, 1360, 50, 159, 288, 589, 930, 1518, 1798, 2987, 60, 187, 336, 681, 1070, 1966, 2320, 3432, 4340, 95, 265, 515, 1052, 1386, 2430, 3475, 4484, 5977, 7495, 110, 303, 584, 1184, 1556, 2718

Offset: 1

Author

Joerg Arndt, Oct 09 2017

Keywords

• nonn
• tabl

Examples

			Triangle begins:
0
1, 7
2, 14, 28
7, 35, 65, 133
10, 47, 86, 198, 316
22, 86, 134, 331, 487, 913
28, 106, 164, 399, 696, 1099, 1360
50, 159, 288, 589, 930, 1518, 1798, 2987
60, 187, 336, 681, 1070, 1966, 2320, 3432, 4340
95, 265, 515, 1052, 1386, 2430, 3475, 4484, 5977, 7495
...
		

Links

• Joerg Arndt, Table of n, a(n) for n = 1..5050 (rows 1..50)
• Wikipedia, Abelian sandpile model

Crossrefs

Cf. A249872.

Formula

T(n,n) = A249872(n).

Conjecture: T(n,1) = A023855(n).