A122684 Sum of all Wiener indices of "chemical" trees described by A000602(n).

0, 1, 4, 19, 54, 155, 432, 1252, 3384, 9714, 26752, 75836, 213058, 603791, 1702868, 4830747, 13666890, 38742120, 109715858, 310884129, 880368618, 2493252951, 7058102770, 19978082407, 56531061316, 159932660960, 452354328946, 1279190479845, 3616595649500

Offset

1,3

Comments

C program, see the first Bomfim link, around the function Gen() of Gang Li & Frank Ruskey.

References

S. Wagner, Graph-theoretical enumeration and digital expansions: an analytic approach, Dissertation, Fakult. f. Tech. Math. u. Tech. Physik, Tech. Univ. Graz, Austria, Feb., 2006.

Links

Table of n, a(n) for n=1..29.

W. Bomfim, C program

Stephan Wagner, On the average Wiener index of degree-restricted trees

Crossrefs

Sequence in context: A166808 A253008 A186310 * A122681 A215862 A174612

Adjacent sequences: A122681 A122682 A122683 * A122685 A122686 A122687

Keyword

nonn

Author

N. J. A. Sloane, Sep 23 2006

Extensions

a(11)-a(29) from Washington Bomfim, Feb 24 2011

Status

approved