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 A169587 #14 Aug 06 2021 15:37:01
%S A169587 3,7,21,74,296,1315,6393,33645,190085,1145246,7318338,49376293,
%T A169587 350384315,2606467211,20266981269,164306340566,1385709542808,
%U A169587 12133083103491,110095025916745,1033601910417425,10024991744613469,100316367530768074,1034373400144455266
%N A169587 The total number of ways of partitioning the multiset {1,1,1,2,3,...,n-2}.
%H A169587 Alois P. Heinz, <a href="/A169587/b169587.txt">Table of n, a(n) for n = 3..576</a>
%H A169587 M. Griffiths, I. Mezo, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL13/Griffiths/griffiths11.html">A generalization of Stirling Numbers of the Second Kind via a special multiset</a>, JIS 13 (2010) #10.2.5.
%H A169587 M. Griffiths, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL12/Griffiths/griffiths7.html">Generalized Near-Bell Numbers</a>, JIS 12 (2009) 09.5.7
%F A169587 For n>=3, a(n)=(Bell(n)+3Bell(n-1)+5Bell(n-2)+2Bell(n-3))/6, where Bell(n) is the n-th Bell number (the Bell numbers are given in A000110).
%F A169587 E.g.f.: (e^(3x)+6e^(2x)+9e^x+2)(e^(e^x-1))/6.
%e A169587 The partitions of {1,1,1,2} are {{1},{1},{1},{2}}, {{1,1},{1},{2}}, {{1,2},{1},{1}}, {{1,1},{1,2}}, {{1,1,1},{2}}, {{1,1,2},{1}} and {{1,1,1,2}}, so a(4)=7.
%t A169587 Table[(BellB[n] + 3 BellB[n - 1] + 5 BellB[n - 2] + 2 BellB[n - 3])/ 6, {n, 3, 23}]
%Y A169587 This is related to A000110, A035098 and A169588.
%Y A169587 Row n=3 of A346426.
%Y A169587 Cf. A346813.
%K A169587 nonn
%O A169587 3,1
%A A169587 _Martin Griffiths_, Dec 02 2009