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 A298446 Triangle T(n,k) read by rows: number of n-node connected graphs with rectilinear crossing number k (k=0..A014540(n)). 1
 1, 1, 2, 6, 20, 1, 99, 11, 1, 1, 646, 149, 38, 15, 1, 2, 1, 0, 0, 1, 5974, 3008, 1251, 542, 171, 80, 47, 12, 15, 7, 4, 1, 3, 0, 0, 1, 0, 0, 0, 1, 71885 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Computed up to n=8 using data provided by Geoffrey Exoo.  (There appear to be some problems with n=9 data.) T(9,1) >= 71335. - Eric W. Weisstein, Mar 28 2019 LINKS Eric Weisstein's World of Mathematics, Connected Graph Eric Weisstein's World of Mathematics, Rectilinear Crossing Number FORMULA T(n,0) = A003094(n). kmax(n) = A014540(n). T(n,kmax(n)) = 1 for n > 4. sum(k=0..kmax(n), T(n,k)) = A001349(n). EXAMPLE Triangle begins: 1 1 2 6 20,1 99,11,1,1 646,149,38,15,1,2,1,0,0,1 5974,3008,1251,542,171,80,47,12,15,7,4,1,3,0,0,1,0,0,0,1 CROSSREFS Cf. A014540 (rectilinear crossing number for K_n). Cf. A298445 (counts for simple graph). Sequence in context: A332406 A127942 A110956 * A205012 A254120 A286426 Adjacent sequences:  A298443 A298444 A298445 * A298447 A298448 A298449 KEYWORD nonn,tabf AUTHOR Eric W. Weisstein, Jan 19 2018 EXTENSIONS Corrected by Eric W. Weisstein, Mar 28 2019 STATUS approved

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Last modified December 7 16:53 EST 2021. Contains 349581 sequences. (Running on oeis4.)