

A193331


Triangle of edge counts for the (n,k)Turan graphs.


2



0, 0, 1, 0, 2, 3, 0, 4, 5, 6, 0, 6, 8, 9, 10, 0, 9, 12, 13, 14, 15, 0, 12, 16, 18, 19, 20, 21, 0, 16, 21, 24, 25, 26, 27, 28, 0, 20, 27, 30, 32, 33, 34, 35, 36, 0, 25, 33, 37, 40, 41, 42, 43, 44, 45, 0, 30, 40, 45, 48, 50, 51, 52, 53, 54, 55, 0, 36, 48, 54, 57, 60, 61, 63, 64, 64, 65, 66
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OFFSET

1,5


COMMENTS

The triangle of t(n,k) begins:
0
0, 1
0, 2, 3
0, 4, 5, 6
0, 6, 8, 9, 10
0, 9, 12, 13, 14, 15


LINKS

Reinhard Zumkeller, Rows n=1..100 of triangle, flattened
P. Erdos, R. J. Faudree, C. C. Rousseau, Extremal problems involving vertices and edges on odd cycles, Disc. Math. 101 (1992) 2331
Eric Weisstein's World of Mathematics, Turan Graph
Eric Weisstein's World of Mathematics, Turans Theorem


FORMULA

t(n,k) = floor((k1)*n^2/(2*k)).


MATHEMATICA

Flatten[Table[Floor[(k  1) n^2/(2k)], {n, 20}, {k, n}]]


PROG

(Haskell)
a193331 n k = a193331_tabl !! (n1) !! (k1)
a193331_tabl = map a193331_row [1..]
a193331_row n = zipWith div (map (* n^2) [0..n1]) (map (2 *) [1..n])
 Reinhard Zumkeller, Aug 08 2011
(PARI) T(n, k)=(k1)*n^2\(2*k) \\ Charles R Greathouse IV, Aug 01 2016


CROSSREFS

Cf. A198787 (another version).
Sequence in context: A011150 A100112 A198787 * A091246 A271439 A133637
Adjacent sequences: A193328 A193329 A193330 * A193332 A193333 A193334


KEYWORD

nonn,nice,tabl,easy,look


AUTHOR

Eric W. Weisstein, Jul 22 2011


STATUS

approved



