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A334280
Irregular table read by rows: T(n, k) is the coefficient of x^k in the chromatic polynomial of the 1-skeleton of the n-dimensional demihypercube, 0 <= k <= 2^(n-1).
1
0, 1, 0, -1, 1, 0, -6, 11, -6, 1, 0, -2790, 7467, -7852, 4300, -1346, 244, -24, 1, 0, -36586695600, 132041735820, -208601259660, 194243767689, -120509323400, 53195294240, -17371817260, 4296667608, -815202340, 119111090, -13339000, 1127752, -69860, 3000, -80, 1
OFFSET
1,7
LINKS
Eric Weisstein's World of Mathematics, Chromatic Polynomial
Eric Weisstein's World of Mathematics, Halved Cube Graph
Wikipedia, Demihypercube
EXAMPLE
n\k| 0 1 2 3 4 5 6 7 8
---+----------------------------------------
1| 0 1
2| 0 -1 1
3| 0 -6 11 -6 1
4| 0 -2790 7467 -7852 4300 -1346 244 -24 1
MATHEMATICA
T[n_, k_] := Coefficient[ChromaticPolynomial[GraphData[{"HalvedCube", n}], x], x, k]
CROSSREFS
Cf. A048994 (simplex), A334278 (hypercube), A334279 (cross-polytope).
Sequence in context: A258054 A106540 A212208 * A134012 A103704 A135998
KEYWORD
sign,tabf
AUTHOR
Peter Kagey, Apr 22 2020
STATUS
approved