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 A296191 Numerators of the Harary index of the n X n grid graph. 1
 0, 5, 133, 293, 3399, 137111, 140351, 4854401, 18690167, 94423807, 2190046361, 11026443655, 11090909287, 323238388599, 4312895221021, 8658059232167, 60805695015569, 2256364094708093, 2262227096103773, 92967638570454913 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS Eric Weisstein's World of Mathematics, Grid Graph Eric Weisstein's World of Mathematics, Harary Index EXAMPLE 0, 5, 133/6, 293/5, 3399/28, 137111/630, 140351/396, ... MATHEMATICA Table[n (2 n + 1) (2 + (2 n - 1) Derivative[1][Log[CatalanNumber[# - 1]] &][n] - n)/3, {n, 20}] // FullSimplify // Numerator Table[n (2 n + 1) (2 + (2 n - 1) (HarmonicNumber[n - 3/2] - HarmonicNumber[n] + 2 Log[2]) - n)/3, {n, 20}] // FunctionExpand // FullSimplify // Numerator CROSSREFS Cf. A296192 (denominators). Sequence in context: A135758 A152794 A053517 * A114474 A280305 A085506 Adjacent sequences:  A296188 A296189 A296190 * A296192 A296193 A296194 KEYWORD nonn,frac AUTHOR Eric W. Weisstein, Dec 07 2017 STATUS approved

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Last modified December 7 09:33 EST 2019. Contains 329843 sequences. (Running on oeis4.)