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A224598
Number of (n+2)X(n+2) 0..2 matrices with each 3X3 subblock idempotent
0
122, 272, 482, 666, 1202, 2092, 3308, 5398, 8876, 14232, 22734, 36346, 57712, 91204, 143828, 226126, 354436, 554296, 865004, 1347042, 2093774, 3248860, 5032926, 7784734, 12023856, 18546144
OFFSET
1,1
COMMENTS
Diagonal of A224606
LINKS
Christian Ballot, Clark Kimberling, and Peter J. C. Moses, Linear Recurrences Originating From Polynomial Trees, Fibonacci Quart. 55 (2017), no. 5, 15-27. Mentions this sequence.
FORMULA
Empirical: a(n) = 6*a(n-1) -15*a(n-2) +23*a(n-3) -30*a(n-4) +36*a(n-5) -34*a(n-6) +27*a(n-7) -21*a(n-8) +13*a(n-9) -6*a(n-10) +3*a(n-11) -a(n-12) for n>14
EXAMPLE
Some solutions for n=3
..1..0..0..0..0....0..1..0..0..2....1..1..1..0..2....1..1..1..0..1
..1..0..0..0..0....0..1..0..0..1....0..0..0..0..0....0..0..0..0..0
..1..0..0..0..0....0..1..0..0..1....0..0..0..0..0....0..0..0..0..0
..2..0..0..0..0....0..1..0..0..1....0..0..0..0..0....2..1..1..1..1
..1..0..0..0..0....0..2..0..0..1....0..2..1..1..1....0..0..0..0..0
CROSSREFS
Sequence in context: A004925 A369598 A276303 * A070955 A195856 A116216
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 11 2013
STATUS
approved