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%I #7 May 11 2024 16:45:41
%S 1,3,9,15,27,45,81,105,135,225,243,315,405,675,729,945,1215,1575,2025,
%T 2187,2835,3375,3645,4725,6075,6561,8505,10125,10395,10935,11025,
%U 14175,18225,19683,23625,25515,30375,31185,32805,33075,42525,50625
%N Numbers that can be written as a product of double factorials of odd numbers.
%t kmax = 60000;
%t maxExponent = 10;
%t ff = Select[TakeWhile[Range[3, kmax], #!! < kmax &]!!, OddQ];
%t lg = Length@ff;
%t iter = Sequence @@ Table[{x[i], 0, maxExponent}, {i, 1, lg}];
%t seq = Table[k = Times @@ Table[ff[[i]]^x[i] , {i, 1, lg}]; If[k <= kmax, k, Nothing], Evaluate@iter] // Flatten // Union (* _Jean-François Alcover_, May 11 2024 *)
%Y Cf. A001013, A001147, A025487, A057863.
%K nonn
%O 1,2
%A _Ilya Gutkovskiy_, May 04 2024
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