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a(n) = Product_{i=1..n} i^s(n,i), where s is an unsigned Stirling number of the 1st kind.
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%I #25 Jul 10 2024 16:02:21

%S 1,1,2,24,5971968,295334114577121602242226794587320483840

%N a(n) = Product_{i=1..n} i^s(n,i), where s is an unsigned Stirling number of the 1st kind.

%H Paolo Xausa, <a href="/A319761/b319761.txt">Table of n, a(n) for n = 0..6</a>

%e For n = 4 we have a(4) = 1^6*2^11*3^6*4^1 = 5971968.

%p f:= n -> mul(i^abs(Stirling1(n,i)),i=1..n):

%p map(f, [$0..6]); # _Robert Israel_, Sep 27 2018

%t A319761[n_] := Product[i^Abs[StirlingS1[n, i]], {i, n}];

%t Array[A319761, 7, 0] (* _Paolo Xausa_, Jul 10 2024 *)

%o (PARI) a(n) = prod(i=1, n, i^abs(stirling(n, i, 1))); \\ _Michel Marcus_, Sep 27 2018

%Y Cf. A132393, A373796.

%K nonn

%O 0,3

%A _Jeffrey Shallit_, Sep 27 2018