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 A323429 #6 Jan 15 2019 09:24:28 %S A323429 1,1,3,5,10,14,26,35,58,81,124,169,257,345,501,684,968,1304,1830,2452, %T A323429 3387,4541,6188,8257,11193,14865,19968,26481,35341,46674,62007,81611, %U A323429 107860,141602,186292,243800,319610,416984,544601,708690,922472,1197018,1553442 %N A323429 Number of rectangular plane partitions of n. %C A323429 Number of ways to fill a (not necessarily square) matrix with the parts of an integer partition of n so that the rows and columns are weakly decreasing. %e A323429 The a(5) = 14 matrices: %e A323429 [5] [4 1] [3 2] [3 1 1] [2 2 1] [2 1 1 1] [1 1 1 1 1] %e A323429 . %e A323429 [4] [3] [2 1] %e A323429 [1] [2] [1 1] %e A323429 . %e A323429 [3] [2] %e A323429 [1] [2] %e A323429 [1] [1] %e A323429 . %e A323429 [2] %e A323429 [1] %e A323429 [1] %e A323429 [1] %e A323429 . %e A323429 [1] %e A323429 [1] %e A323429 [1] %e A323429 [1] %e A323429 [1] %t A323429 Table[Sum[Length[Select[Union[Sort/@Tuples[IntegerPartitions[#,{k}]&/@ptn]],And@@OrderedQ/@Transpose[#]&]],{ptn,IntegerPartitions[n]},{k,Min[ptn]}],{n,30}] %Y A323429 Cf. A000219, A003293, A047966, A101509, A114736, A117433, A299968, A319066. %Y A323429 Cf. A323301, A323307, A323430, A323431, A323432, A323435, A323436, A323438. %K A323429 nonn %O A323429 0,3 %A A323429 _Gus Wiseman_, Jan 15 2019