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A319761
a(n) = Product_{i=1..n} i^s(n,i), where s is an unsigned Stirling number of the 1st kind.
2
1, 1, 2, 24, 5971968, 295334114577121602242226794587320483840
OFFSET
0,3
LINKS
EXAMPLE
For n = 4 we have a(4) = 1^6*2^11*3^6*4^1 = 5971968.
MAPLE
f:= n -> mul(i^abs(Stirling1(n, i)), i=1..n):
map(f, [$0..6]); # Robert Israel, Sep 27 2018
MATHEMATICA
A319761[n_] := Product[i^Abs[StirlingS1[n, i]], {i, n}];
Array[A319761, 7, 0] (* Paolo Xausa, Jul 10 2024 *)
PROG
(PARI) a(n) = prod(i=1, n, i^abs(stirling(n, i, 1))); \\ Michel Marcus, Sep 27 2018
CROSSREFS
Sequence in context: A365617 A159932 A100010 * A045510 A226325 A065665
KEYWORD
nonn
AUTHOR
Jeffrey Shallit, Sep 27 2018
STATUS
approved