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 A068724 Number of solenoidal flows (flow in = flow out) in a 5 X 5 square array with integer velocities -n .. n. 3

%I

%S 1,569397,1305759171,251611610655,13336307324915,322309309862183

%N Number of solenoidal flows (flow in = flow out) in a 5 X 5 square array with integer velocities -n .. n.

%e Sample flows (. represents a space):

%e Numbers in long rows are on cell walls showing velocity rightward.

%e Numbers in long columns are on cell floors showing velocity downwards.

%e 5 X 5 cell centers are at the intersection of long rows and long columns.

%e n=1:

%e .. 0 . 0 . 0 . 0 . 0

%e .0. -1. -1. -1. -1 . 0

%e .. 1 . 0 . 0 . 0. -1

%e .0 . 0. -1. -1 . 0 . 0

%e .. 1 . 1 . 0. -1. -1

%e .0 . 0 . 0 . 0 . 0 . 0

%e .. 1 . 1 . 0. -1. -1

%e .0 . 0 . 1 . 1 . 0 . 0

%e .. 1 . 0 . 0 . 0. -1

%e .0 . 1 . 1 . 1 . 1 . 0

%e .. 0 . 0 . 0 . 0 . 0

%e n=2:

%e .. 0 . 0 . 0 . 0 . 0

%e .0. -2. -1. -1. -1 . 0

%e .. 2. -1 . 0 . 0. -1

%e .0 . 0. -2. -2. -1 . 0

%e .. 2 . 1 . 0. -1. -2

%e .0 . 0. -1. -1 . 0 . 0

%e .. 2 . 2 . 0. -2. -2

%e .0 . 0 . 2 . 2 . 0 . 0

%e .. 2 . 0 . 0 . 0. -2

%e .0 . 2 . 2 . 2 . 2 . 0

%e .. 0 . 0 . 0 . 0 . 0

%Y Cf. 2 X 2=1, 3, 5, 7..., 3 X 3 A068722, 4 X 4 A068723, 6x6 A068725, by velocity limit 1..13 A068726-A068738.

%K nonn

%O 0,2

%A _R. H. Hardin_, Feb 26 2002

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Last modified June 7 01:26 EDT 2020. Contains 334836 sequences. (Running on oeis4.)