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A224618
Number of (n+4)X5 0..2 matrices with each 5X5 subblock idempotent
1
54182, 20465, 23914, 32029, 39001, 43489, 54070, 79918, 122542, 187631, 273520, 383006, 535709, 762005, 1106184, 1626730, 2385788, 3471665, 5021971, 7252751, 10500500, 15253690, 22196507, 32295594, 46934366, 68138057, 98892534
OFFSET
1,1
COMMENTS
Column 1 of A224625
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) -a(n-2) +a(n-3) -2*a(n-4) +2*a(n-5) -a(n-7) -a(n-9) +a(n-10) -a(n-11) +a(n-12) for n>18
EXAMPLE
Some solutions for n=2
..0..0..0..0..0....0..0..0..0..0....0..0..0..0..0....1..2..0..1..0
..0..0..0..0..0....1..1..2..0..0....1..1..2..0..0....0..0..0..0..0
..0..0..0..0..0....0..0..0..0..0....0..0..0..0..0....0..1..1..2..0
..0..0..0..0..2....0..0..0..0..0....0..0..0..0..0....0..0..0..0..0
..0..0..0..0..1....0..0..0..0..0....0..0..0..0..0....0..0..0..0..0
..0..0..0..0..1....0..1..1..1..1....0..2..2..2..1....2..0..0..1..1
CROSSREFS
Sequence in context: A202467 A224617 A224625 * A254263 A254256 A254302
KEYWORD
nonn
AUTHOR
R. H. Hardin Apr 12 2013
STATUS
approved