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f-vectors for simplicial complexes of dimension at most 2 on at most n-1 vertices.
2

%I #10 Sep 19 2012 06:02:49

%S 2,3,5,10,25,70,190,471,1060,2189,4203,7592,13027,21400,33868,51901,

%T 77334,112423,159905,223062,305789,412666,549034,721075,935896,

%U 1201617,1527463,1923860,2402535,2976620,3660760,4471225,5426026

%N f-vectors for simplicial complexes of dimension at most 2 on at most n-1 vertices.

%F a(n+1)= (2*n^6 -6*n^5 +5*n^4 +60*n^3 -7*n^2 +306*n +720)/360 fits terms up to 5426026. [_Frank Ellermann_]

%F Empirical G.f.: -x*(x^6-7*x^5+25*x^4-32*x^3+26*x^2-11*x+2)/(x-1)^7. [_Colin Barker_, Sep 19 2012]

%Y Cf. A011826.

%K nonn

%O 1,1

%A Svante Linusson (linusson(AT)math.kth.se)