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A290344
Denominators of the Kirchhoff (and Harary) index for the n-hypercube graph.
1
1, 1, 1, 3, 3, 15, 15, 105, 105, 315, 63, 693, 693, 9009, 9009, 45045, 45045, 765765, 765765, 14549535, 14549535, 14549535, 14549535, 334639305, 334639305, 1673196525, 1673196525, 5019589575, 5019589575, 145568097675, 145568097675, 4512611027925, 4512611027925
OFFSET
0,4
LINKS
Eric Weisstein's World of Mathematics, Harary Index
Eric Weisstein's World of Mathematics, Hypercube Graph
Eric Weisstein's World of Mathematics, Kirchhoff Index
EXAMPLE
Kirchhoff (and Harary) indices are 0, 1, 5, 58/3, 206/3, 3548/15, 12136/15, 291824/105, 1012048/105, ....
MATHEMATICA
Table[-2^(n - 1) HarmonicNumber[n] - 4^n Re[LerchPhi[2, 1, n + 1]], {n, 0, 32}] // Denominator
Table[2^(-1 + n) n HypergeometricPFQ[{1, 1, 1 - n}, {2, 2}, -1], {n, 0, 32}] // Denominator (* Eric W. Weisstein, Dec 11 2017 *)
CROSSREFS
Cf. A290343 (numerators).
Sequence in context: A100735 A362531 A129356 * A217858 A185275 A055634
KEYWORD
nonn,frac
AUTHOR
Eric W. Weisstein, Jul 28 2017
STATUS
approved