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A256045 Triangle read by rows: order of all-2s 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 (list; table; graph; refs; listen; history; text; internal format)
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

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Last modified July 13 05:18 EDT 2020. Contains 335673 sequences. (Running on oeis4.)