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A224573
Number of (n+5)X9 0..1 matrices with each 6X6 subblock idempotent
1
18868, 6411, 6659, 7394, 8143, 8714, 9164, 10807, 13624, 17332, 21731, 26592, 31785, 38491, 47899, 60907, 78205, 100219, 127312, 161005, 203975, 259809, 332836, 427756, 549639, 705073, 903350, 1157341, 1484238, 1905898, 2449315, 3148048
OFFSET
1,1
COMMENTS
Column 4 of A224577
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) -4*a(n-2) +4*a(n-3) -3*a(n-4) +a(n-5) +2*a(n-6) -5*a(n-7) +6*a(n-8) -6*a(n-9) +4*a(n-10) -a(n-11) -a(n-12) +2*a(n-13) -2*a(n-14) +2*a(n-15) -a(n-16) for n>20
EXAMPLE
Some solutions for n=2
..1..0..0..0..0..0..0..0..0....1..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..0
..0..0..1..0..0..0..1..1..0....0..0..0..0..0..0..0..0..0
..0..0..1..0..0..0..1..1..0....0..0..0..0..0..0..0..0..0
..0..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..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
CROSSREFS
Sequence in context: A330839 A243134 A212077 * A342080 A251015 A277787
KEYWORD
nonn
AUTHOR
R. H. Hardin Apr 10 2013
STATUS
approved