%I #28 Feb 19 2024 04:08:11
%S 1,1,8,648,663552,10368000000,2902376448000000,
%T 16731622649806848000000,2245680377810414777401344000000,
%U 7830203310981140781182893575634944000000,783020331098114078118289357563494400000000000000000,2457453226667794121573260254679367673480373862400000000000000000
%N a(n) = Product_{k = 1..n} k^(k + 1).
%H G. C. Greubel, <a href="/A267968/b267968.txt">Table of n, a(n) for n = 0..35</a>
%F a(n) = n! * A002109(n). - _Vaclav Kotesovec_, Jan 26 2016
%F a(n) = (n!)^2 * abs(A203421(n)). - _Michel Marcus_, Feb 11 2016
%p a:= proc(n) a(n):= `if`(n=0, 1, a(n-1)*n^(n+1)) end:
%p seq(a(n), n=0..12); # _Alois P. Heinz_, Feb 10 2016
%t a[n_]:= Product[k^(k+1), {k,n}]; Table[a[n], {n, 0, 20}]
%t Table[Hyperfactorial[n]*n!, {n, 0, 15}] (* _Vaclav Kotesovec_, Jan 26 2016 *)
%o (Magma) [&*[k^(k+1): k in [1..n]]: n in [1..11]]; // _Vincenzo Librandi_, Jan 23 2016
%o (PARI) a(n) = prod(k=1, n, k^(k+1)); \\ _Michel Marcus_, Jan 23 2016
%o (SageMath) [product(k^(k+1) for k in range(1,n+1)) for n in range(21)] # _G. C. Greubel_, Feb 18 2024
%Y Cf. A002109 (Product_{k = 1..n} k^k), A203421 (Product_{k = 1..n} k^(k-1), up to sign).
%K nonn
%O 0,3
%A _José María Grau Ribas_, Jan 22 2016