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A279980
Number of 4Xn 0..1 arrays with no element equal to a strict majority of its horizontal and antidiagonal neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.
1
0, 31, 296, 1922, 10491, 50690, 226771, 963728, 3941732, 15655280, 60749739, 231325874, 867192006, 3208394065, 11737643962, 42526452550, 152777627539, 544782076812, 1929805835927, 6795769111934, 23804414728200, 82983605105905
OFFSET
1,2
COMMENTS
Row 4 of A279977.
FORMULA
Empirical recurrence of order 68 (see link above)
EXAMPLE
Some solutions for n=4
..0..0..1..0. .0..1..1..0. .0..1..0..1. .0..1..1..0. .0..1..0..0
..1..0..0..1. .1..0..1..1. .1..0..1..0. .1..0..1..1. .0..1..0..1
..0..1..1..0. .1..0..0..1. .0..0..1..0. .1..1..0..0. .0..0..1..0
..0..0..1..1. .1..1..0..0. .1..0..0..1. .1..0..1..0. .1..1..0..1
CROSSREFS
Cf. A279977.
Sequence in context: A221430 A115151 A327561 * A369173 A001298 A027841
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 24 2016
STATUS
approved