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A224648 Number of (n+2)X7 0..1 matrices with each 3X3 subblock having the same population 1
22400, 31232, 44096, 64256, 115328, 215744, 430208, 1012928, 2472320, 6281600, 17169536, 47643584, 134253440, 388421312, 1130324096, 3308544896, 9779374208, 28974513344, 86050337408, 256534766528, 765559245440, 2286911361920 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 5 of A224651

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..84

FORMULA

Empirical: a(n) = 6*a(n-1) -11*a(n-2) +42*a(n-3) -216*a(n-4) +396*a(n-5) -719*a(n-6) +3018*a(n-7) -5533*a(n-8) +6498*a(n-9) -20880*a(n-10) +38280*a(n-11) -33444*a(n-12) +75384*a(n-13) -138204*a(n-14) +97848*a(n-15) -134784*a(n-16) +247104*a(n-17) -150336*a(n-18) +93312*a(n-19) -171072*a(n-20) +93312*a(n-21)

EXAMPLE

Some solutions for n=2

..1..0..0..1..0..1..1....1..0..1..0..0..1..0....1..0..0..0..0..0..0

..0..0..1..0..1..1..0....0..0..0..0..1..1..1....0..0..1..0..0..1..0

..1..1..1..1..0..0..1....0..1..1..1..0..0..0....0..1..0..1..1..0..1

..0..1..0..0..1..1..0....1..1..0..0..1..0..0....1..0..0..0..0..0..0

CROSSREFS

Sequence in context: A154094 A206656 A329787 * A237215 A230924 A250441

Adjacent sequences:  A224645 A224646 A224647 * A224649 A224650 A224651

KEYWORD

nonn

AUTHOR

R. H. Hardin Apr 13 2013

STATUS

approved

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Last modified December 1 10:26 EST 2021. Contains 349427 sequences. (Running on oeis4.)