A207030 - OEIS

A207030

Number of 7Xn 0..1 arrays avoiding 0 0 0 and 0 1 1 horizontally and 0 0 1 and 1 0 1 vertically

14, 196, 546, 2646, 10374, 28224, 95900, 263228, 707756, 1914436, 4765030, 11929281, 28919940, 68405886, 160363388, 367794936, 834116976, 1868512272, 4133596062, 9061947202, 19668851743, 42331019322, 90400217730, 191610354448

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Row 7 of A207024

LINKS

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

FORMULA

Empirical: a(n) = 7*a(n-1) -9*a(n-2) -31*a(n-3) +31*a(n-4) +213*a(n-5) -162*a(n-6) -750*a(n-7) +51*a(n-8) +2425*a(n-9) +794*a(n-10) -4554*a(n-11) -4713*a(n-12) +5817*a(n-13) +9762*a(n-14) -282*a(n-15) -12462*a(n-16) -7428*a(n-17) +1841*a(n-18) +10627*a(n-19) +10332*a(n-20) +5076*a(n-21) -13128*a(n-22) -16008*a(n-23) -6153*a(n-24) +11991*a(n-25) +11817*a(n-26) +9499*a(n-27) -3106*a(n-28) -8556*a(n-29) -11907*a(n-30) -573*a(n-31) +3822*a(n-32) +7314*a(n-33) +2562*a(n-34) +1026*a(n-35) -3630*a(n-36) -2274*a(n-37) -1530*a(n-38) +1026*a(n-39) +594*a(n-40) +1050*a(n-41) +50*a(n-42) -50*a(n-43) -405*a(n-44) -49*a(n-45) -77*a(n-46) +69*a(n-47) +21*a(n-48) +39*a(n-49) -12*a(n-50) -6*a(n-52) -a(n-54) +a(n-55)

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Sequence in context: A207732 A208691 A207604 * A207175 A207458 A208004

Adjacent sequences: A207027 A207028 A207029 * A207031 A207032 A207033

KEYWORD

nonn

AUTHOR

R. H. Hardin Feb 14 2012

STATUS

approved