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A329789
Total number of graceful labelings of connected graphs with n vertices and n edges.
2
0, 0, 2, 12, 68, 400, 2496, 17338, 127660, 1030524, 8852398, 82121018, 806839236, 8481362264, 93933923996, 1104325114202
OFFSET
1,3
COMMENTS
In general, consider a connected graph with E edges and V vertices. The vertices are given labels in the range 0 to E so that the differences between edges' endpoints are {1,...,E}. None of the vertices are isolated; hence each vertex label participates in at least one edge. For this sequence E = V = n.
CROSSREFS
Cf. A033472 (V=E+1), A329788 (any V). A diagonal of the triangle in A329790.
Sequence in context: A377112 A128103 A359489 * A245854 A078839 A243771
KEYWORD
nonn,more
AUTHOR
N. J. A. Sloane, Dec 01 2019, based on email from Don Knuth, Dec 01 2019
STATUS
approved