A005645 Number of sensed 3-connected planar maps with n edges. (Formerly M0599)

1, 0, 1, 2, 3, 4, 15, 32, 89, 266, 797, 2496, 8012, 26028, 85888, 286608, 965216, 3278776, 11221548, 38665192, 134050521, 467382224, 1638080277, 5768886048, 20407622631, 72494277840, 258527335373, 925322077852, 3323258053528, 11973883092034, 43273374700200, 156836969693756, 569967330200576, 2076647113454878, 7584534277720818, 27764845224462192, 101862027752012402, 374484866509396780, 1379489908513460150

Offset

6,4

References

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

Links

N. J. A. Sloane, Table of n, a(n) for n = 6..50

T. R. S. Walsh, Number of sensed planar maps with n edges and m vertices

T. R. S. Walsh, Counting nonisomorphic three-connected planar maps, J. Combin. Theory Ser. B 32 (1982), no. 1, 33-44.

Formula

a(n) = Sum_{k=4..n-2} A239893(k, n+2-k). - Andrew Howroyd, Mar 27 2021

Crossrefs

Cf. A002840 (unsensed), A239893.

Sequence in context: A270929 A103096 A295757 * A362639 A348628 A281586

Adjacent sequences: A005642 A005643 A005644 * A005646 A005647 A005648

Keyword

nonn

Author

N. J. A. Sloane

Extensions

More terms and b-file added by N. J. A. Sloane, May 08 2012

Status

approved