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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.

%I A293452 #19 Mar 11 2022 07:46:34
%S A293452 0,1,7,2,14,28,7,35,65,133,10,47,86,198,316,22,86,134,331,487,913,28,
%T A293452 106,164,399,696,1099,1360,50,159,288,589,930,1518,1798,2987,60,187,
%U A293452 336,681,1070,1966,2320,3432,4340,95,265,515,1052,1386,2430,3475,4484,5977,7495,110,303,584,1184,1556,2718
%N 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.
%H A293452 Joerg Arndt, <a href="/A293452/b293452.txt">Table of n, a(n) for n = 1..5050</a> (rows 1..50)
%H A293452 Wikipedia, <a href="https://en.wikipedia.org/wiki/Abelian_sandpile_model">Abelian sandpile model</a>
%F A293452 T(n,n) = A249872(n).
%F A293452 Conjecture: T(n,1) = A023855(n).
%e A293452 Triangle begins:
%e A293452 0
%e A293452 1, 7
%e A293452 2, 14, 28
%e A293452 7, 35, 65, 133
%e A293452 10, 47, 86, 198, 316
%e A293452 22, 86, 134, 331, 487, 913
%e A293452 28, 106, 164, 399, 696, 1099, 1360
%e A293452 50, 159, 288, 589, 930, 1518, 1798, 2987
%e A293452 60, 187, 336, 681, 1070, 1966, 2320, 3432, 4340
%e A293452 95, 265, 515, 1052, 1386, 2430, 3475, 4484, 5977, 7495
%e A293452 ...
%Y A293452 Cf. A249872.
%K A293452 nonn,tabl
%O A293452 1,3
%A A293452 _Joerg Arndt_, Oct 09 2017