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A224554 Number of (n+2) X 5 0..1 matrices with each 3 X 3 subblock idempotent. 1
113, 133, 180, 230, 320, 451, 620, 866, 1229, 1746, 2493, 3586, 5178, 7498, 10891, 15855, 23117, 33749, 49321, 72130, 105545, 154505, 226246, 331373, 485430, 711197, 1042059, 1526945, 2237564, 3279010, 4805306, 7042184, 10320470, 15125013 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Column 3 of A224559.
LINKS
FORMULA
Empirical: a(n) = 4*a(n-1) - 6*a(n-2) + 5*a(n-3) - 4*a(n-4) + 3*a(n-5) - a(n-6) for n>8.
Empirical g.f.: x*(113 - 319*x + 326*x^2 - 257*x^3 + 267*x^4 - 156*x^5 + 20*x^6 + 5*x^7) / ((1 - x)^3*(1 - x - x^3)). - Colin Barker, Aug 31 2018
EXAMPLE
Some solutions for n=3:
..1..0..0..1..0....0..0..0..0..0....1..1..0..0..0....1..1..1..1..1
..1..0..0..1..0....0..0..0..0..0....0..0..0..0..0....0..0..0..0..0
..1..0..0..1..0....0..0..0..0..0....0..0..0..0..0....0..0..0..0..0
..1..0..0..1..0....0..0..0..0..0....0..0..0..0..0....0..0..0..0..0
..0..0..0..1..0....0..0..1..1..1....1..0..1..1..1....0..0..0..0..0
CROSSREFS
Cf. A224559.
Sequence in context: A344627 A187867 A216288 * A095617 A139645 A240584
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 10 2013
STATUS
approved

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Last modified July 24 15:34 EDT 2024. Contains 374584 sequences. (Running on oeis4.)