A039660 Related to enumeration of edge-rooted catafusenes.

0, 0, 0, 1, 2, 8, 14, 43, 72, 204, 336, 926, 1516, 4144, 6772, 18504, 30236, 82844, 135452, 372581, 609710, 1684220, 2758730, 7652531, 12546332, 34941752, 57337172, 160280987, 263224802, 738363872, 1213502942, 3414804517

Offset: 1

Author

N. J. A. Sloane

Keywords

• nonn

Comments

Let b(n>=0) = 0, 0, 0, 0, 1, 0, 6, 0, 29, 0, 132, 0, 590, 0, 2628, ... be the

"aerated" version of A045445. This sequence is the convolution of A040000 and b. - R. J. Mathar, Jul 30 2019

Links

• S. J. Cyvin et al., Enumeration and classification of benzenoid systems. 32. Normal perifusenes with two internal vertices, J. Chem. Inform. Comput. Sci., 32 (1992), 532-540.

Formula

G.f.: (1+x)[1-6x^2+7x^4-(1-3x^2)sqrt(1-6x^2+5x^4)]/[2x^4(1-x)] (eq. (11) in Cyvin et al.)

Extensions

More terms from Emeric Deutsch, Mar 14 2004