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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.

A342913 Pairwise listing of the partitions of 2k into two parts, (s,t), with 0 < t <= s ordered by decreasing values of s and where k = 1,2,... .

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%I A342913 #6 Mar 28 2021 19:34:24
%S A342913 1,1,3,1,2,2,5,1,4,2,3,3,7,1,6,2,5,3,4,4,9,1,8,2,7,3,6,4,5,5,11,1,10,
%T A342913 2,9,3,8,4,7,5,6,6,13,1,12,2,11,3,10,4,9,5,8,6,7,7,15,1,14,2,13,3,12,
%U A342913 4,11,5,10,6,9,7,8,8,17,1,16,2,15,3,14,4,13,5,12,6,11,7
%N A342913 Pairwise listing of the partitions of 2k into two parts, (s,t), with 0 < t <= s ordered by decreasing values of s and where k = 1,2,... .
%H A342913 <a href="/index/Par#part">Index entries for sequences related to partitions</a>
%F A342913 a(n) = k - (k^2 + k - m)*(-1)^n / 2, where k = round(sqrt(m)) and m = 2*floor((n+1-(-1)^n)/2).
%F A342913 a(n) = A342769(A103889(n)).
%e A342913                                                         [13,1]
%e A342913                                                [11,1]   [12,2]
%e A342913                                        [9,1]   [10,2]   [11,3]
%e A342913                                [7,1]   [8,2]   [9, 3]   [10,4]
%e A342913                        [5,1]   [6,2]   [7,3]   [8, 4]   [9, 5]
%e A342913                [3,1]   [4,2]   [5,3]   [6,4]   [7, 5]   [8, 6]
%e A342913        [1,1]   [2,2]   [3,3]   [4,4]   [5,5]   [6, 6]   [7, 7]
%e A342913    2k    2       4       6       8       10      12       14
%e A342913   --------------------------------------------------------------------------
%e A342913    2k   Decreasing partitions of 2k
%e A342913   --------------------------------------------------------------------------
%e A342913    2   1,1
%e A342913    4   3,1,2,2
%e A342913    6   5,1,4,2,3,3
%e A342913    8   7,1,6,2,5,3,4,4
%e A342913   10   9,1,8,2,7,3,6,4,5,5
%e A342913   12   11,1,10,2,9,3,8,4,7,5,6,6
%e A342913   14   13,1,12,2,11,3,10,4,9,5,8,6,7,7
%e A342913   ...
%Y A342913 Cf. A000194, A052928, A103889, A339399, A339443, A342769.
%K A342913 nonn
%O A342913 1,3
%A A342913 _Wesley Ivan Hurt_, Mar 28 2021