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 A320886 #8 Oct 26 2018 20:36:36 %S A320886 1,1,3,5,10,14,25,33,54,73,107,140,207,264,369,479,652,828,1112,1400, %T A320886 1848,2326,3009,3762,4856,6020,7648,9478,11942,14705,18427,22576, %U A320886 28083,34350,42429,51714,63680,77289,94618,114648,139773,168799,205144,247128,299310,359958,434443,521255,627812,751665,902862 %N A320886 Number of multiset partitions of integer partitions of n where all parts have the same product. %e A320886 The a(1) = 1 through a(6) = 25 multiset partitions: %e A320886 (1) (2) (3) (4) (5) (6) %e A320886 (11) (12) (13) (14) (15) %e A320886 (1)(1) (111) (22) (23) (24) %e A320886 (1)(11) (112) (113) (33) %e A320886 (1)(1)(1) (1111) (122) (114) %e A320886 (2)(2) (1112) (123) %e A320886 (1)(111) (11111) (222) %e A320886 (11)(11) (2)(12) (1113) %e A320886 (1)(1)(11) (1)(1111) (1122) %e A320886 (1)(1)(1)(1) (11)(111) (3)(3) %e A320886 (1)(1)(111) (11112) %e A320886 (1)(11)(11) (111111) %e A320886 (1)(1)(1)(11) (12)(12) %e A320886 (1)(1)(1)(1)(1) (2)(112) %e A320886 (2)(2)(2) %e A320886 (1)(11111) %e A320886 (11)(1111) %e A320886 (111)(111) %e A320886 (1)(1)(1111) %e A320886 (1)(11)(111) %e A320886 (11)(11)(11) %e A320886 (1)(1)(1)(111) %e A320886 (1)(1)(11)(11) %e A320886 (1)(1)(1)(1)(11) %e A320886 (1)(1)(1)(1)(1)(1) %t A320886 sps[{}]:={{}};sps[set:{i_,___}]:=Join@@Function[s,Prepend[#,s]&/@sps[Complement[set,s]]]/@Cases[Subsets[set],{i,___}]; %t A320886 mps[set_]:=Union[Sort[Sort/@(#/.x_Integer:>set[[x]])]&/@sps[Range[Length[set]]]]; %t A320886 Table[Length[Select[Join@@mps/@IntegerPartitions[n],SameQ@@Times@@@#&]],{n,8}] %o A320886 (PARI) %o A320886 G(n)={my(M=Map()); for(k=1, n, forpart(p=k, my(t=vecprod(Vec(p)), z); mapput(M, t, if(mapisdefined(M, t, &z), z, 0) + x^k))); M} %o A320886 a(n)=if(n==0, 1, vecsum(apply(p->EulerT(Vecrev(p/x, n))[n], Mat(G(n))[,2]))) \\ _Andrew Howroyd_, Oct 26 2018 %Y A320886 Cf. A001055, A001970, A045778, A050336, A279375, A294617, A294786, A294787, A294788, A320887, A320888, A320889. %K A320886 nonn %O A320886 0,3 %A A320886 _Gus Wiseman_, Oct 23 2018 %E A320886 a(13)-a(50) from _Andrew Howroyd_, Oct 26 2018