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A290348
Denominators of the Harary index for the n-halved cube graph.
1
1, 1, 1, 1, 1, 3, 3, 3, 1, 5, 5, 15, 15, 105, 105, 105, 105, 315, 315, 315, 315, 3465, 3465, 3465, 693, 9009, 3003, 3003, 3003, 5005, 5005, 5005, 5005, 85085, 17017, 153153, 153153, 2909907, 2909907, 14549535
OFFSET
1,6
LINKS
Eric Weisstein's World of Mathematics, Halved Cube Graph
Eric Weisstein's World of Mathematics, Hypercube Graph
EXAMPLE
First few terms are 0, 1, 6, 26, 100, 1096/3, 3920/3, 13936/3, 16544, 296256/5, ....
MATHEMATICA
Table[-2^(n - 1) HarmonicNumber[n] - 2^(2 n - 1) Re[LerchPhi[2, 1, n + 1]], {n, 20}] // Denominator
CROSSREFS
Cf. A290347 (numerators).
Sequence in context: A201277 A163644 A339901 * A014465 A226645 A243095
KEYWORD
nonn,frac
AUTHOR
Eric W. Weisstein, Jul 28 2017
STATUS
approved