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 A120711 7 X 7 matrix Matrov of seven vertex Fano Plane: Characteristic polynomial : 12 + 10 x - 24 x^2 - 21 x^3 + 12 x^4 + 12 x^5 - x^7. 0
 0, 14, 32, 150, 492, 1894, 6724, 24854, 89972, 329238, 1197972, 4372054, 15930580, 58096214, 211770452, 772129110, 2814859092, 10262536534, 37414140244, 136403674454, 497291840852, 1813006427478, 6609762501972, 24097566365014 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 COMMENTS Limited here to seven connecting lines in the bonding graph. REFERENCES (*http://mathworld.wolfram.com/FanoPlane.html*) LINKS FORMULA M = {{0, 1, 0, 0, 0, 1, 1}, {1, 0, 1, 0, 0, 0, 1}, {0, 1, 0, 1, 0, 0, 1}, {0, 0, 1, 0, 1, 0, 1}, {0, 0, 0, 1, 0, 1, 1}, {1, 0, 0, 0, 1, 0, 1}, {1, 1, 1, 1, 1, 1, 0}} v[1] = {0, 1, 1, 2, 3, 5, 8} v[n_] := v[n] = M.v[n - 1] a(n) =v[n][[1]]. Empirical G.f.: 2*x*(7+16*x-2*x^2-14*x^3)/((1-x)*(1+x)*(1+2*x)*(1-2*x-6*x^2)). [Colin Barker, Mar 26 2012] MATHEMATICA M = {{0, 1, 0, 0, 0, 1, 1}, {1, 0, 1, 0, 0, 0, 1}, {0, 1, 0, 1, 0, 0, 1}, {0, 0, 1, 0, 1, 0, 1}, {0, 0, 0, 1, 0, 1, 1}, {1, 0, 0, 0, 1, 0, 1}, {1, 1, 1, 1, 1, 1, 0}} v[1] = {0, 1, 1, 2, 3, 5, 8} v[n_] := v[n] = M.v[n - 1] a = Table[v[n][[1]], {n, 1, 50}] CROSSREFS Cf. A111384. Sequence in context: A084194 A031109 A155819 * A018959 A225420 A107484 Adjacent sequences:  A120708 A120709 A120710 * A120712 A120713 A120714 KEYWORD nonn AUTHOR Roger Bagula, Aug 12 2006 STATUS approved

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Last modified May 24 01:37 EDT 2013. Contains 225613 sequences.