This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A330223 #23 May 03 2025 07:44:15
%S A330223 1,1,4,5,12,9,30,17,52,44,94,58,211,103,302,242,552,299,1024,492,1592,
%T A330223 1007,2523,1257,4636,2000,6661,3705,10823,4567,18147,6844,26606,12272,
%U A330223 40766,15056,67060,21639,95884,37357,146781,44585,230098,63263,330889,106619,491182,124756
%N A330223 Number of non-isomorphic achiral multiset partitions of weight n.
%C A330223 A multiset partition is a finite multiset of finite nonempty multisets. It is achiral if it is not changed by any permutation of the vertices.
%e A330223 Non-isomorphic representatives of the a(1) = 1 through a(5) = 9 multiset partitions:
%e A330223 {1} {11} {111} {1111} {11111}
%e A330223 {12} {123} {1122} {12345}
%e A330223 {1}{1} {1}{11} {1234} {1}{1111}
%e A330223 {1}{2} {1}{1}{1} {1}{111} {11}{111}
%e A330223 {1}{2}{3} {11}{11} {1}{1}{111}
%e A330223 {11}{22} {1}{11}{11}
%e A330223 {12}{12} {1}{1}{1}{11}
%e A330223 {1}{1}{11} {1}{1}{1}{1}{1}
%e A330223 {1}{2}{12} {1}{2}{3}{4}{5}
%e A330223 {1}{1}{1}{1}
%e A330223 {1}{1}{2}{2}
%e A330223 {1}{2}{3}{4}
%e A330223 Non-isomorphic representatives of the a(6) = 30 multiset partitions:
%e A330223 {111111} {1}{11111} {1}{1}{1111} {1}{1}{1}{111} {1}{1}{1}{1}{11}
%e A330223 {111222} {11}{1111} {1}{11}{111} {1}{1}{11}{11} {1}{1}{2}{2}{12}
%e A330223 {112233} {111}{111} {11}{11}{11} {1}{2}{11}{22}
%e A330223 {123456} {111}{222} {11}{12}{22} {1}{2}{12}{12}
%e A330223 {112}{122} {11}{22}{33} {1}{2}{3}{123} {1}{1}{1}{1}{1}{1}
%e A330223 {12}{1122} {1}{2}{1122} {1}{1}{1}{2}{2}{2}
%e A330223 {123}{123} {12}{12}{12} {1}{1}{2}{2}{3}{3}
%e A330223 {12}{13}{23} {1}{2}{3}{4}{5}{6}
%Y A330223 Planted achiral trees are A003238.
%Y A330223 Achiral set-systems are counted by A083323.
%Y A330223 BII-numbers of achiral set-systems are A330217.
%Y A330223 Achiral integer partitions are counted by A330224.
%Y A330223 Non-isomorphic fully chiral multiset partitions are A330227.
%Y A330223 MM-numbers of achiral multisets of multisets are A330232.
%Y A330223 Achiral factorizations are A330234.
%Y A330223 Cf. A001055, A007716, A283877, A317533, A330098, A330233.
%K A330223 nonn,hard
%O A330223 0,3
%A A330223 _Gus Wiseman_, Dec 07 2019
%E A330223 a(10)-a(11) and a(13) from _Erich Friedman_, Nov 20 2024
%E A330223 a(12) from _Bert Dobbelaere_, Apr 29 2025
%E A330223 More terms from _Bert Dobbelaere_, May 02 2025