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%I #11 Mar 30 2012 18:40:21
%S 11,22,33,121,132,231,1221,1232,1331,2321,2332,12221,12232,12331,
%T 13321,13332,23221,23232,23331,122221,122232,122331,123321,123332,
%U 133221,133232,133331,232221,232232,232331,233321,233332,1222221,1222232
%N List of molecules in Hintze-Adami artificial chemistry (see comments for definition).
%C These molecules are composed of three types of atoms called 1, 2 and 3. The atoms are arranged linearly. Each atom shares bonds with the adjacent atoms. Each atom must carry as many bonds as the numeral representing it.
%C The members of this sequence are arranged in numerical order.
%C The reference states that the molecules "are numbered according to their complexity (length and type of atoms)", which is ambiguous.
%C For n > 2 there are fibonacci(n+1) members of length n.
%C Hintze and Adami arbitrarily chose a maximum length of 12, resulting in 608 total members; the last is 233333333332.
%C All terms are divisible by 11.
%H Arend Hintze and Christoph Adami, <a href="http://arXiv.org/abs/0705.4674">Evolution of complex modular biological networks</a>. Page 3 defines the set of valid molecules; p. 17 lists a(0) through a(5) and a(607).
%e Using "-" to represent single bonds and "=" to represent double bonds, some members are a(0) = 1-1, a(4) = 2=3-1 and a(607) = 2=3-3=3-3=3-3=3-3=3-3=2.
%e 2222 is not a member because the first 2 must share two bonds with the second 2, so the second 2 has no bonds left to share with the third 2.
%Y Cf. A000045.
%K base,easy,fini,nonn
%O 0,1
%A _Jonathan Vos Post_, Jun 03 2007
%E Edited and extended by _David Wasserman_, Mar 05 2008