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URL: https://oeis.org/A007122

⇱ A007122 - OEIS

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A007122
Number of unlabeled identity connected unit interval graphs with n nodes.
2
0, 0, 0, 0, 0, 2, 4, 15, 36, 108, 276, 770, 2036, 5586, 15072, 41370, 113184, 312488, 863824, 2401344, 6692368, 18724990, 52531788, 147824963, 417006316, 1179285900, 3342274092, 9492427854, 27011049612, 76999988534
OFFSET
1,6
REFERENCES
R. W. Robinson, personal communication.
R. W. Robinson, Numerical implementation of graph counting algorithms, AGRC Grant, Math. Dept., Univ. Newcastle, Australia, 1980.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
CROSSREFS
Cf. A005219.
Sequence in context: A196260 A073814 A181442 * A005219 A153945 A153942
KEYWORD
nonn,nice
STATUS
approved