cp's OEIS Frontend

A056613 Number of n-celled pseudo still lifes in Conway's Game of Life, up to rotation and reflection.

%I A056613 #47 Jan 09 2020 12:19:09
%S A056613 0,0,0,0,0,0,0,1,1,7,16,55,110,279,620,1645,4067,10843,27250,70637,
%T A056613 179011,462086,1184882,3069135,7906676,20463274,52816265,136655095,
%U A056613 353198379,914075620,2364815358,6123084116,15851861075,41058173683
%N A056613 Number of n-celled pseudo still lifes in Conway's Game of Life, up to rotation and reflection.
%C A056613 There are two slightly different possible definitions for a pseudo still life: a still life that can be partitioned into exactly two different still lifes, or a still life that can be partitioned into two *or more* still lifes. This sequence uses the latter definition. The first point in the sequence where this makes a difference is a(32) = 6123084116, which would be a(32) = 6123084115 under the former definition. - _Nathaniel Johnston_, May 25 2017
%H A056613 S. Ekström, <a href="http://conwaylife.com/forums/viewtopic.php?p=38931#p38931">Enumerating Still Lifes (in C)</a>
%H A056613 Mark D. Niemiec, <a href="http://codercontest.com/mniemiec/objcount.htm">Life Object Counts</a>
%e A056613 For n = 8, the unique pseudo still life is a pair of 2 X 2 blocks occupying a 5 X 2 bounding box.
%Y A056613 Cf. A019473, A330283.
%K A056613 nonn,hard,more
%O A056613 1,10
%A A056613 _N. J. A. Sloane_, Aug 28 2000
%E A056613 a(24) corrected by _Nathaniel Johnston_, Aug 26 2016 at the suggestion of Mark Niemiec
%E A056613 a(25)-a(30) computed by Simon Ekström and inserted by _Adam P. Goucher_, Jan 08 2017
%E A056613 a(24) corrected by _Nathaniel Johnston_, Feb 21 2017 (computed by Simon Ekström)
%E A056613 a(31)-a(32) from _Nathaniel Johnston_, using a script made by Simon Ekström, May 25 2017
%E A056613 a(33) from _Nathaniel Johnston_, using a script made by Simon Ekström, Apr 05 2019
%E A056613 a(34) from _Nathaniel Johnston_, using a script made by Simon Ekström, Jan 09 2020