cp's OEIS Frontend

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.

A319761 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 A319761 #25 Jul 10 2024 16:02:21
%S A319761 1,1,2,24,5971968,295334114577121602242226794587320483840
%N A319761 a(n) = Product_{i=1..n} i^s(n,i), where s is an unsigned Stirling number of the 1st kind.
%H A319761 Paolo Xausa, <a href="/A319761/b319761.txt">Table of n, a(n) for n = 0..6</a>
%e A319761 For n = 4 we have a(4) = 1^6*2^11*3^6*4^1 = 5971968.
%p A319761 f:= n -> mul(i^abs(Stirling1(n,i)),i=1..n):
%p A319761 map(f, [$0..6]); # _Robert Israel_, Sep 27 2018
%t A319761 A319761[n_] := Product[i^Abs[StirlingS1[n, i]], {i, n}];
%t A319761 Array[A319761, 7, 0] (* _Paolo Xausa_, Jul 10 2024 *)
%o A319761 (PARI) a(n) = prod(i=1, n, i^abs(stirling(n, i, 1))); \\ _Michel Marcus_, Sep 27 2018
%Y A319761 Cf. A132393, A373796.
%K A319761 nonn
%O A319761 0,3
%A A319761 _Jeffrey Shallit_, Sep 27 2018