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%I M1288 #14 Dec 19 2021 00:11:33
%S 0,0,0,0,0,2,4,15,36,108,276,770,2036,5586,15072,41370,113184,312488,
%T 863824,2401344,6692368,18724990,52531788,147824963,417006316,
%U 1179285900,3342274092,9492427854,27011049612,76999988534
%N Number of unlabeled identity connected unit interval graphs with n nodes.
%D R. W. Robinson, personal communication.
%D R. W. Robinson, Numerical implementation of graph counting algorithms, AGRC Grant, Math. Dept., Univ. Newcastle, Australia, 1980.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H R. W. Robinson, <a href="/A007122/b007122.txt">Table of n, a(n) for n = 1..190</a>
%Y Cf. A005219.
%K nonn,nice
%O 1,6
%A _N. J. A. Sloane_