A005977 Reduced interval graphs with n nodes. (Formerly M1787)

0, 0, 0, 0, 1, 2, 7, 31, 168, 1025, 7013, 52495, 425213, 3696032, 34291937, 338161526, 3532185118, 38963334652, 452704892533, 5526901638291, 70746674291507

Offset

1,6

References

P. J. Hanlon, personal communication.

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Links

Table of n, a(n) for n=1..21.

Phil Hanlon, Counting interval graphs, Trans. Amer. Math. Soc. 272 (1982), no. 2, 383-426.

Crossrefs

Sequence in context: A193657 A007164 A321208 * A199675 A352309 A059037

Adjacent sequences: A005974 A005975 A005976 * A005978 A005979 A005980

Keyword

nonn

Author

N. J. A. Sloane.

Status

approved