

A256045


Triangle read by rows: order of all2s configuration on the n X k sandpile grid graph.


4



1, 7, 8, 5, 71, 3, 9, 679, 77, 52, 13, 769, 281, 17753, 29, 47, 3713, 4271, 726433, 434657, 272, 17, 8449, 2245, 33507, 167089, 46069729, 901, 123, 81767, 8569, 24852386, 265721, 8118481057, 190818387, 73124, 89, 93127, 18061, 20721019, 4213133, 4974089647, 1031151241, 1234496016491, 89893
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OFFSET

2,2


COMMENTS

It seems that T(2*k, 2) = A195549(k); true at least up to k = 16. If there was column 1, then T(k, 1) would seem to coincide with A005246(k+2).  Andrey Zabolotskiy, Jul 21 2018


LINKS

Table of n, a(n) for n=2..46.
Laura Florescu, Daniela Morar, David Perkinson, Nicholas Salter, Tianyuan Xu, Sandpiles and Dominos, Electronic Journal of Combinatorics, Volume 22(1), 2015.


EXAMPLE

Triangle begins:
[1]
[7, 8]
[5, 71, 3]
[9, 679, 77, 52]
[13, 769, 281, 17753, 29]
[47, 3713, 4271, 726433, 434657, 272]
[17, 8449, 2245, 33507, 167089, 46069729, 901]
[123, 81767, 8569, 24852386, 265721, 8118481057, 190818387, 73124]
[89, 93127, 18061, 20721019, 4213133, 4974089647, 1031151241, 1234496016491, 89893]
...


CROSSREFS

Main diagonal gives A256046, A256043, and A256047.
Cf. A005246, A195549.
Sequence in context: A117239 A198365 A262898 * A004496 A197762 A181624
Adjacent sequences: A256042 A256043 A256044 * A256046 A256047 A256048


KEYWORD

nonn,tabl


AUTHOR

N. J. A. Sloane, Mar 15 2015


STATUS

approved



