cp's OEIS Frontend

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.

A387121 Array read by antidiagonals: T(n,k) is the number of sets of k integer sided cuboids with distinct volumes that fill an n X n X n cube.

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%I A387121 #16 Aug 25 2025 19:13:09
%S A387121 1,0,1,0,0,1,0,0,1,1,0,0,2,1,1,0,0,4,3,2,1,0,0,2,11,8,2,1,0,0,1,26,47,
%T A387121 11,3,1,0,0,0,55,206,77,19,3,1,0,0,0,48,793,442,183,23,4,1,0,0,0,23,
%U A387121 2653,2451,1531,259,35,4,1,0,0,0,0,6706,13022,12178
%N A387121 Array read by antidiagonals: T(n,k) is the number of sets of k integer sided cuboids with distinct volumes that fill an n X n X n cube.
%C A387121 The partitions here must be valid packings of the n X n X n cube, hence T(n,k) is generally less than the number of partitions of n^3 into distinct cuboids (x,y,z) with 1 <= x,y,z <= n and no pair of triplets having equal volume x*y*z.
%F A387121 T(n,1) = 1, T(n,k) = 0 for k > n^3.
%e A387121 Array begins:
%e A387121   1     0     0     0     0
%e A387121   1     0     0     0     0
%e A387121   1     1     2     4     2
%e A387121   1     1     3    11    26
%e A387121   1     2     8    47   206
%e A387121   1     2    11    77   442
%e A387121   1     3    19   183  1531
%e A387121   1     3    23   259  2661
%e A387121   1     4    35   457  5574
%e A387121   1     4    40   599  8514
%e A387121   ...
%Y A387121 Columns are A004526 (k=2), A381847 (k=3), A385580 (k=4), A387040 (k=5).
%K A387121 tabl,nonn,new
%O A387121 1,13
%A A387121 _Janaka Rodrigo_, Aug 16 2025
%E A387121 More terms from _Sean A. Irvine_, Aug 25 2025