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 A300121 #8 May 24 2018 16:10:05 %S A300121 1,1,2,2,4,5,8,4,11,12,16,12,32,28,31,8,64,31,128,33,82,64,256,28,69, %T A300121 144,69,86,512,105,1024,16,208,320,209,82,2048,704,512,86,4096,318, %U A300121 8192,216,262,1536,16384,64,465,262,1232,528,32768,209,588,245,2912,3328 %N A300121 Number of normal generalized Young tableaux, of shape the integer partition with Heinz number n, with all rows and columns weakly increasing and all regions connected skew partitions. %C A300121 The diagram of a connected skew partition is required to be connected as a polyomino but can have empty rows or columns. A generalized Young tableau of shape y is an array obtained by replacing the dots in the Ferrers diagram of y with positive integers. A tableau is normal if its entries span an initial interval of positive integers. The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k). %e A300121 The a(9) = 11 tableaux: %e A300121 1 1 %e A300121 1 1 %e A300121 . %e A300121 2 1 1 1 1 1 1 2 %e A300121 1 1 1 2 2 2 1 2 %e A300121 . %e A300121 1 1 1 2 1 2 1 3 %e A300121 2 3 1 3 3 3 2 3 %e A300121 . %e A300121 1 2 1 3 %e A300121 3 4 2 4 %t A300121 undcon[y_]:=Select[Tuples[Range[0,#]&/@y],Function[v,GreaterEqual@@v&&With[{r=Select[Range[Length[y]],y[[#]]=!=v[[#]]&]},Or[Length[r]<=1,And@@Table[v[[i]]<y[[i+1]],{i,Range[Min@@r,Max@@r-1]}]]]]]; %t A300121 cos[y_]:=cos[y]=With[{sam=Most[undcon[y]]},If[Length[sam]===0,If[Total[y]===0,{{}},{}],Join@@Table[Prepend[#,y]&/@cos[sam[[k]]],{k,1,Length[sam]}]]]; %t A300121 primeMS[n_]:=If[n===1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]]; %t A300121 Table[Length[cos[Reverse[primeMS[n]]]],{n,50}] %Y A300121 Cf. A000085, A000898, A056239, A006958, A138178, A153452, A238690, A259479, A259480, A296150, A296561, A297388, A299699, A299925, A299926, A300056, A300060, A300118, A300120, A300122, A300123, A300124. %K A300121 nonn %O A300121 1,3 %A A300121 _Gus Wiseman_, Feb 25 2018