%I #8 Nov 19 2019 05:56:54
%S 2,5,63,70633,25090373284177
%N Number of independent subsets of nodes of 3^n cube (P_3 X ... X P_3).
%H Sean A. Irvine, <a href="https://github.com/archmageirvine/joeis/blob/master/src/irvine/oeis/a027/A027667.java">Java program</a> (github)
%e For n=0, the two sets are the empty set and a set containing a single isolated vertex. - _Sean A. Irvine_, Nov 16 2019
%Y Cf. A027624 (P_2), A027668 (P_4).
%K nonn,nice,hard,more
%O 0,1
%A _R. H. Hardin_
%E a(0) corrected by _Sean A. Irvine_, Nov 16 2019