A203084 Number of (n+2) X 3 binary arrays avoiding patterns 000 and 101 in rows and columns.
98, 253, 621, 1575, 4000, 10057, 25384, 64140, 161819, 408415, 1031041, 2602296, 6568305, 16579362, 41847510, 105626421, 266611217, 672949667, 1698582936, 4287374163, 10821707646, 27314936026, 68945297129, 174023973205
Offset: 1
Keywords
Examples
Some solutions for n=3: 1 0 0 1 1 0 1 1 0 0 1 0 0 0 1 1 1 1 1 0 0 1 1 0 1 1 0 1 1 1 1 0 0 1 1 1 1 1 0 1 1 0 1 1 1 1 1 1 1 1 1 0 0 1 1 0 0 1 1 0 0 1 1 1 1 1 0 1 1 1 1 1 0 1 1 1 0 0 0 1 1 0 1 1 0 1 0 0 0 1 0 1 0 1 1 0 0 1 1 0 0 1 1 0 0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A203091.
Formula
Empirical: a(n) = a(n-1) + a(n-2) + 6*a(n-3) + 2*a(n-4) + 3*a(n-5) - a(n-6) - a(n-8) - a(n-9) - a(n-10).
Empirical g.f.: x*(98 + 155*x + 270*x^2 + 113*x^3 + 90*x^4 - 44*x^5 - 26*x^6 - 61*x^7 - 53*x^8 - 36*x^9) / (1 - x - x^2 - 6*x^3 - 2*x^4 - 3*x^5 + x^6 + x^8 + x^9 + x^10). - Colin Barker, Mar 03 2018
Comments