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Number of stereoisomers of all n-node acyclic hydrocarbons with no triple bonds.
2

%I #23 Nov 20 2020 20:45:30

%S 1,2,3,9,20,64,205,747,2767,10850,43254,176990,735007,3099272,

%T 13220407,57001841,248009246,1087947441,4807232915,21381055533,

%U 95660032110,430298114499,1945096434552,8832200860663,40271358004756,184325394540531,846667179332120

%N Number of stereoisomers of all n-node acyclic hydrocarbons with no triple bonds.

%C Alternatively, unrooted steric quartic trees allowing single and double edges with n nodes. - _Natan Arie Consigli_, Jun 30 2017

%C Read has incorrect a(10)=14159. - _Sean A. Irvine_, Nov 20 2020

%H Sean A. Irvine, <a href="https://github.com/archmageirvine/joeis/blob/master/src/irvine/oeis/a036/A036673.java">Java program</a> (github)

%H Sean A. Irvine, <a href="/A036672/a036672.pdf">Correction of A036672(10) and A036673(10)</a>, 2020

%H R. C. Read, <a href="/A000598/a000598.pdf">The Enumeration of Acyclic Chemical Compounds</a>, pp. 25-61 of A. T. Balaban, ed., Chemical Applications of Graph Theory, Ac. Press, 1976. [Annotated scanned copy] See p. 60.

%Y Cf. A000628 (steric quartic trees with no double edges).

%K nonn

%O 1,2

%A _N. J. A. Sloane_

%E Name clarified by _Natan Arie Consigli_, Jun 30 2017

%E a(10) corrected and more terms from _Sean A. Irvine_, Nov 20 2020