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A093854 Triangle read by rows: T(n,m) = number of 3-uniform T_0-hypergraphs with n distinct edges and m vertices(n>=3, 1<=m<=2*n+1). 0
0, 0, 0, 4, 80, 480, 840, 0, 0, 0, 1, 200, 3840, 27720, 77280, 45360, 0, 0, 0, 0, 252, 14664, 263844, 2192400, 8709120, 13819680, 3991680, 0, 0, 0, 0, 210, 38340, 1518790, 26267360, 240765840, 1205492400, 3068881200, 3180038400, 605404800 (list; graph; refs; listen; history; text; internal format)
OFFSET
3,4
LINKS
FORMULA
E.g.f.: (1+x)*exp(-x+x^2/2+x^3/3*y)*Sum((1+y)^binomial(n, 3)*exp(-x^2*(1+y)^n/2)*x^n/n!, n=0..infinity).
EXAMPLE
0,0,0,4,80,480,840; 0,0,0,1,200,3840,27720,77280,45360; 0,0,0,0,252,14664,263844,2192400,8709120,13819680,3991680; ...
CROSSREFS
Sequence in context: A204296 A192790 A211152 * A345459 A366955 A269146
KEYWORD
nonn,tabf
AUTHOR
Goran Kilibarda, Vladeta Jovovic, May 21 2004
STATUS
approved

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Last modified March 28 18:04 EDT 2024. Contains 371254 sequences. (Running on oeis4.)