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A146257
Number of n X n binary arrays symmetric under horizontal reflection with all ones connected only in a 110-111-101 pattern in any orientation.
0
1, 1, 1, 1, 1, 1, 105, 241, 1729, 3313, 39657, 104401, 2969697, 9697625, 3123603217, 14435373673, 2122314213377, 11094314340193, 1937878683810145, 12836441729414657, 6546745088072698929, 53161394239931798437
OFFSET
1,7
EXAMPLE
Maximal 8 X 8 example
.1.1.0.0.0.0.1.1
.1.1.1.0.0.1.1.1
.1.0.1.0.0.1.0.1
.0.0.0.0.0.0.0.0
.0.0.0.0.0.0.0.0
.1.0.1.0.0.1.0.1
.1.1.1.0.0.1.1.1
.0.1.1.0.0.1.1.0
CROSSREFS
Sequence in context: A262723 A250757 A350199 * A075764 A046299 A010090
KEYWORD
nonn
AUTHOR
STATUS
approved