Search: id:A056877 Results 1-1 of 1 results found. %I A056877 %S A056877 0,1,1,1,1,2,3,4,4,8,10,15,17,30,35,60,64,117,128,236,241,459,476, %T A056877 937,912,1813,1789,3706 %N A056877 Number of polyominoes with n cells, symmetric about axis 2. %C A056877 This sequence counts polyominoes with exactly the symmetry group D_4 generated by horizontal and vertical reflections. %D A056877 D. H. Redelmeier, Counting polyominoes: yet another attack, Discrete Math., 36 (1981), 191-203. %H A056877 Tomas Oliveira e Silva, Enumeration of polyominoes %H A056877 D. H. Redelmeier, Table 3 of Counting polyominoes... %Y A056877 Cf. A000105, A001168, A006746, A056877, A006748, A056878, A006747, A006749. %Y A056877 Sequences classifying polyominoes by symmetry group: A000105, A006746, A006747, A006748, A006749, A056877, A056878, A142886, A144553, A144554. %Y A056877 Sequence in context: A028298 A047966 A097093 this_sequence A118263 A102539 A118022 %Y A056877 Adjacent sequences: A056874 A056875 A056876 this_sequence A056878 A056879 A056880 %K A056877 nonn %O A056877 1,6 %A A056877 N. J. A. Sloane (njas(AT)research.att.com), Sep 03 2000 Search completed in 0.001 seconds