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.

A318399 Number of triples of set partitions of {1,...,n} with meet {{1},...,{n}} and join {{1,...,n}}.

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%I A318399 #5 Aug 27 2018 22:34:19
%S A318399 1,6,84,2226,93246,5616492,459173406,48933260388,6595445513412,
%T A318399 1098326915060730,221772386369110242,53460963703982862534,
%U A318399 15185890964240671486740,5026315912246843181692776,1919721040169845172603949966,838872819016448052585038291124
%N A318399 Number of triples of set partitions of {1,...,n} with meet {{1},...,{n}} and join {{1,...,n}}.
%F A318399 Logarithmic transform of A318398.
%e A318399 The a(2) = 6 triples:
%e A318399   {{1},{2}} {{1},{2}}  {{1,2}}
%e A318399   {{1},{2}}  {{1,2}}  {{1},{2}}
%e A318399   {{1},{2}}  {{1,2}}   {{1,2}}
%e A318399    {{1,2}}  {{1},{2}} {{1},{2}}
%e A318399    {{1,2}}  {{1},{2}}  {{1,2}}
%e A318399    {{1,2}}   {{1,2}}  {{1},{2}}
%t A318399 nn=20;
%t A318399 Table[n!*SeriesCoefficient[Log[1+Sum[x^k/k!*Sum[StirlingS1[k,i]*BellB[i]^3,{i,0,k}],{k,nn}]],{x,0,n}],{n,nn}]
%Y A318399 Cf. A000110, A000258, A001247, A008277, A048994, A059849, A060639, A181939, A318389, A318390, A318391, A318392, A318393, A318398.
%K A318399 nonn
%O A318399 1,2
%A A318399 _Gus Wiseman_, Aug 25 2018