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Revision History for A181215 (Bold, blue-underlined text is an addition; faded, red-underlined text is a deletion.)

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Number of nX4 binary matrices with no three 1's adjacent in a line diagonally or antidiagonally
(history; published version)
#3 by Russ Cox at Sat Mar 31 12:35:49 EDT 2012
AUTHOR

_R. H. Hardin (rhhardin(AT)att.net) _ Oct 10 2010

Discussion
Sat Mar 31
12:35
OEIS Server: https://oeis.org/edit/global/875
#2 by N. J. A. Sloane at Thu Nov 11 07:34:06 EST 2010
LINKS

R. H. Hardin, <a href="/A181215/b181215.txt">Table of n, a(n) for n=1..225</a>

KEYWORD

nonn,new

nonn

#1 by N. J. A. Sloane at Wed Oct 20 03:00:00 EDT 2010
NAME

Number of nX4 binary matrices with no three 1's adjacent in a line diagonally or antidiagonally

DATA

16, 256, 2500, 28561, 337561, 3857296, 44408896, 512750736, 5909458129, 68121522001, 785456787600, 9055597599504, 104402987257284, 1203692301444361, 13877652596295601, 159998643202876416, 1844662908618342400

OFFSET

1,1

COMMENTS

Column 4 of A181217

LINKS

R. H. Hardin, <a href="b181215.txt">Table of n, a(n) for n=1..225</a>

FORMULA

Empirical: a(n)=11*a(n-1)+16*a(n-2)-24*a(n-3)-906*a(n-4)-2624*a(n-5)+11414*a(n-6)+14042*a(n-7)+444*a(n-8)-92598*a(n-9)-52264*a(n-10)+100166*a(n-11)+77798*a(n-12)-14516*a(n-13)-50238*a(n-14)+950832*a(n-15)-91514*a(n-16)-1551794*a(n-17)-699816*a(n-18)+414094*a(n-19)+1438537*a(n-20)+72931*a(n-21)-647214*a(n-22)+142392*a(n-23)+31008*a(n-24)-44992*a(n-25)+6816*a(n-26)+2496*a(n-27)-256*a(n-28)

EXAMPLE

Some avoided solutions for 3X4

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

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

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

KEYWORD

nonn,new

AUTHOR

R. H. Hardin (rhhardin(AT)att.net) Oct 10 2010

STATUS

approved