A323586 Number of plane partitions of n with no repeated rows (or, equivalently, no repeated columns).
1, 1, 2, 5, 8, 16, 30, 53, 89, 158, 265, 443, 735, 1197
Offset: 0
Examples
The a(4) = 8 plane partitions with no repeated rows: 4 31 22 211 1111 . 3 21 111 1 1 1 The a(6) = 30 plane partitions with no repeated columns: 6 51 42 321 . 5 4 41 3 31 32 31 22 21 221 211 1 2 1 3 2 1 11 2 21 1 11 . 4 3 31 2 21 22 21 111 1 2 1 2 2 1 11 11 1 1 1 2 1 1 1 1 . 3 2 21 11 1 2 1 11 1 1 1 1 1 1 1 1 . 2 11 1 1 1 1 1 1 1 1 . 1 1 1 1 1 1
Crossrefs
Programs
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Mathematica
primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]]; facs[n_]:=If[n<=1,{{}},Join@@Table[Map[Prepend[#,d]&,Select[facs[n/d],Min@@#>=d&]],{d,Rest[Divisors[n]]}]]; ptnplane[n_]:=Union[Map[Reverse@*primeMS,Join@@Permutations/@facs[n],{2}]]; Table[Sum[Length[Select[ptnplane[Times@@Prime/@y],And[UnsameQ@@#,And@@GreaterEqual@@@#,And@@(GreaterEqual@@@Transpose[PadRight[#]])]&]],{y,IntegerPartitions[n]}],{n,10}]