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A181262 T(n,k)=Number of (n+2)X(k+2) binary matrices with every 3X3 block having exactly four 1's 9
126, 336, 336, 906, 746, 906, 2484, 1684, 1684, 2484, 7218, 3942, 3190, 3942, 7218, 21024, 10348, 6360, 6360, 10348, 21024, 61398, 27554, 14974, 10818, 14974, 27554, 61398, 182520, 74784, 36244, 22512, 22512, 36244, 74784, 182520, 542754, 212570 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Table starts

.....126.....336.....906....2484....7218...21024...61398..182520..542754

.....336.....746....1684....3942...10348...27554...74784..212570..608476

.....906....1684....3190....6360...14974...36244...91122..247372..681262

....2484....3942....6360...10818...22512...48846..112500..289830..764832

....7218...10348...14974...22512...41374...79324..162882..387076..952462

...21024...27554...36244...48846...79324..133850..242784..526226.1196428

...61398...74784...91122..112500..162882..242784..386406..750312.1548594

..182520..212570..247372..289830..387076..526226..750312.1297322.2384308

..542754..608476..681262..764832..952462.1196428.1548594.2384308.3873790

.1614492.1755630.1906656.2072106.2438184.2877078.3449484.4777806.6881880

LINKS

R. H. Hardin, Table of n, a(n) for n=1..219

FORMULA

Empirical column 1: a(n)=3*a(n-1)+12*a(n-3)-36*a(n-4)-27*a(n-6)+81*a(n-7)

Empirical column 2: a(n)=4*a(n-1)-3*a(n-2)+32*a(n-3)-128*a(n-4)+96*a(n-5)-375*a(n-6)+1500*a(n-7)-1125*a(n-8)+1980*a(n-9)-7920*a(n-10)+5940*a(n-11)-4644*a(n-12)+18576*a(n-13)-13932*a(n-14)+3888*a(n-15)-15552*a(n-16)+11664*a(n-17)

Empirical columns 3 and 4: a(n)=4*a(n-1)-3*a(n-2)+36*a(n-3)-144*a(n-4)+108*a(n-5)-503*a(n-6)+2012*a(n-7)-1509*a(n-8)+3480*a(n-9)-13920*a(n-10)+10440*a(n-11)-12564*a(n-12)+50256*a(n-13)-37692*a(n-14)+22464*a(n-15)-89856*a(n-16)+67392*a(n-17)-15552*a(n-18)+62208*a(n-19)-46656*a(n-20)

Empirical columns 5 and 6: 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 3X3

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

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

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

CROSSREFS

Sequence in context: A249190 A254465 A063334 * A181255 A322542 A323759

Adjacent sequences:  A181259 A181260 A181261 * A181263 A181264 A181265

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin Oct 10 2010

STATUS

approved

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Last modified June 17 19:10 EDT 2019. Contains 324198 sequences. (Running on oeis4.)