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 A387259 #17 Sep 02 2025 22:54:26
%S A387259 1,1,2,3,6,9,18,28,52,86,151,246,431,694,1167,1884,3095,4904,7919,
%T A387259 12379,19596,30315,47117,71922,110332,166403,251547,375575,560787,
%U A387259 828276,1223544,1789656,2616001,3793295,5491711,7895309,11333811,16164595,23013551,32584816
%N A387259 Number of unordered pairs of partitions of n with the same number of parts.
%C A387259 The corresponding sequence for ordered pairs of partitions is A238312.
%H A387259 Alois P. Heinz, <a href="/A387259/b387259.txt">Table of n, a(n) for n = 0..1000</a>
%F A387259 a(n) = Sum_{k=0..n} A000217(A072233(n,k)).
%F A387259 a(n) = A380126(n) - A380124(n).
%e A387259 For example, a(4)=6: (4,4) (3+1,3+1) (3+1,2+2) (2+2,2+2) (2+1+1,2+1+1) (1+1+1+1,1+1+1+1).
%e A387259 Note that (3+1,2+2) and (2+2,3+1) are not both counted.
%Y A387259 Cf. A380124, A380126, A008284, A072233, A238312.
%K A387259 nonn,new
%O A387259 0,3
%A A387259 _Aidan Markey_, Aug 24 2025