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A089937
Number of 6 X n matrices with entries {0,1} without adjacent 0's in any row or column. 6th row of A089934.
6
21, 239, 2999, 36787, 454385, 5598861, 69050253, 851302029, 10496827403, 129422885699, 1595777230271, 19675706193157, 242599324206721, 2991220223776445, 36881397137844409, 454743263319217787, 5606930966068061311, 69132797971282998447
OFFSET
1,1
COMMENTS
Row/columns 1 through 7 are A000045, A001333, A051736, A051737, A089936, A089937, A089938.
Number of independent vertex sets in the grid graph P_6 X P_n. - Andrew Howroyd, Jun 06 2017
LINKS
FORMULA
G.f.: x*(21 + 71*x - 215*x^2 - 385*x^3 + 668*x^4 + 234*x^5 - 400*x^6 + 9*x^7 + 49*x^8 - 3*x^9 - x^10) / (1 - 8*x - 62*x^2 + 78*x^3 + 375*x^4 - 300*x^5 - 486*x^6 + 385*x^7 + 30*x^8 - 52*x^9 + 2*x^10 + x^11) (conjectured). - Colin Barker, Jun 06 2017
The above conjecture is correct because the order of the recurrence is A089935(6) = 11. - Andrew Howroyd, Dec 24 2019
CROSSREFS
KEYWORD
nonn
AUTHOR
Marc LeBrun, Nov 15 2003
EXTENSIONS
Terms a(17) and beyond from Andrew Howroyd, Jun 06 2017
STATUS
approved