A207722 Number of 7Xn 0..1 arrays avoiding 0 0 0 and 0 0 1 horizontally and 0 0 1 and 1 0 0 vertically.
35, 1225, 20265, 383845, 7070805, 131365535, 2433018665, 45118588165, 836245602255, 15502908395345, 287374205431845, 5327241881287515, 98752480429363705, 1830617909878465155, 33934818950365745265
Offset: 1
Keywords
Examples
Some solutions for n=4 ..0..1..1..0....1..0..1..0....1..1..0..0....0..1..1..1....1..0..1..0 ..1..1..0..1....1..1..0..1....0..1..0..0....1..1..0..1....0..1..0..1 ..0..1..1..1....0..1..1..1....1..1..0..0....1..1..1..1....1..1..1..0 ..1..0..1..1....1..1..1..1....0..1..0..0....1..0..1..0....0..1..0..1 ..0..1..0..1....1..0..1..0....1..1..0..0....1..1..0..1....1..0..1..1 ..1..0..1..1....0..1..0..1....1..1..0..0....1..1..1..1....1..1..1..1 ..0..1..1..0....1..1..1..1....0..1..0..0....1..0..1..1....1..0..1..0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Formula
Empirical: a(n) = 9*a(n-1) +204*a(n-2) -218*a(n-3) -5837*a(n-4) +7253*a(n-5) +53229*a(n-6) -91405*a(n-7) -159544*a(n-8) +385275*a(n-9) +60956*a(n-10) -516325*a(n-11) +117854*a(n-12) +297983*a(n-13) -97139*a(n-14) -89135*a(n-15) +26027*a(n-16) +14356*a(n-17) -2512*a(n-18) -1087*a(n-19) +37*a(n-20) +20*a(n-21)
Comments