A107278 - OEIS

%I #12 May 24 2019 17:32:56

%S 1,4,17,60,209,685,2204,6913,21387,65241,197104,590284,1755804,

%T 5191723,15276610,44761350,130682371,380337474,1103927291,3196494453

%N Number of spiro bicyclic skeletons with n carbon atoms.

%C See Parks et al. for precise definition. Sequence is last column of table III.

%H Camden A. Parks and James B. Hendrickson, <a href="https://dokumen.tips/documents/enumeration-of-monocyclic-and-bicyclic-carbon-skeletons.html">Enumeration of monocyclic and bicyclic carbon skeletons</a>, J. Chem. Inf. Comput. Sci., vol. 31, 334-339 (1991).

%Y Table III of the Parks et al. reference has 4 sequences: A121158, A121159, A121160 and this sequence.

%K nonn

%O 6,2

%A _N. J. A. Sloane_, Sep 10 2006

%E Incorrect g.f. removed by _Georg Fischer_, May 24 2019