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A224683 Number of (n+4)X5 0..1 matrices with each 5X5 subblock idempotent 1
5682, 2351, 2662, 3465, 4405, 5385, 6713, 8897, 12393, 17893, 25853, 36869, 52253, 74230, 106404, 154071, 224107, 325892, 472847, 684866, 991959, 1438581, 2089095, 3035865, 4411494, 6407917, 9304859, 13510805, 19621025, 28500115, 41401620 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 1 of A224690

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

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

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

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

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

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

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

CROSSREFS

Sequence in context: A151770 A224682 A224690 * A222824 A183638 A192098

Adjacent sequences:  A224680 A224681 A224682 * A224684 A224685 A224686

KEYWORD

nonn

AUTHOR

R. H. Hardin Apr 15 2013

STATUS

approved

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Last modified December 6 06:14 EST 2021. Contains 349563 sequences. (Running on oeis4.)