A202050 Number of (n+2) X 8 binary arrays avoiding patterns 001 and 110 in rows and columns.
1392, 5216, 15760, 41088, 95984, 205792, 411696, 777760, 1400080, 2418432, 4030832, 6511456, 10232400, 15689792, 23534800, 34610112, 49992496, 71042080, 99459024, 137348288, 187293232, 252438816, 336585200, 444292576, 580998096
Offset: 1
Keywords
Examples
Some solutions for n=3: 0 0 0 0 0 0 0 0 0 1 0 1 0 1 0 1 1 0 1 1 1 1 1 1 0 1 0 1 0 0 0 0 1 0 1 0 1 0 0 0 0 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 1 0 1 0 1 1 0 1 1 1 1 1 1 0 1 0 1 0 0 0 0 0 1 0 1 0 0 0 0 0 1 0 0 0 0 0 0 0 1 0 1 0 0 0 0 0 1 0 1 0 1 0 1 1 0 1 0 1 0 0 0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A202052.
Formula
Empirical: a(n) = (1/1260)*n^8 + (11/315)*n^7 + (59/90)*n^6 + (308/45)*n^5 + (7807/180)*n^4 + (7667/45)*n^3 + (14139/35)*n^2 + (17876/35)*n + 256.
Conjectures from Colin Barker, May 26 2018: (Start)
G.f.: 16*x*(87 - 457*x + 1183*x^2 - 1869*x^3 + 1925*x^4 - 1307*x^5 + 567*x^6 - 143*x^7 + 16*x^8) / (1 - x)^9.
a(n) = 9*a(n-1) - 36*a(n-2) + 84*a(n-3) - 126*a(n-4) + 126*a(n-5) - 84*a(n-6) + 36*a(n-7) - 9*a(n-8) + a(n-9) for n>9.
(End)
Comments