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%I #20 Feb 28 2024 10:50:04
%S 1,1,1,2,1,6,1,16,3,10,1,1728,1,14,15,1024,1,5832,1,8000,21,22,1,
%T 191102976,5,26,81,21952,1,24300000,1,1048576,33,34,35,470184984576,1,
%U 38,39,4096000000,1,130691232,1,85184,91125,46,1,64925062108545024,7,125000,51
%N a(n) = Product_{d|n} (pod(d)/d) where pod(k) is the product of the divisors of k (A007955).
%F a(n) = n for n = 1 and squarefree semiprimes (A006881).
%e For n = 6; a(6) = pod(1)/1 * pod(2)/2 * pod(3)/3 * pod(6)/6 = 1/1 * 2/2 * 3/3 * 36/6 = 6.
%t Array[Product[Apply[Times, Divisors@ d]/d, {d, Divisors@ #}] &, 51] (* _Michael De Vlieger_, Jan 19 2019 *)
%o (Magma) [&*[&*[c: c in Divisors(d)] / d: d in Divisors(n)]: n in [1..100]]
%o (PARI) a(n) = my(x=1); fordiv(n, d, x*=vecprod(divisors(d))/d); x; \\ _Michel Marcus_, Dec 23 2018
%Y Cf. A006881, A007955, A322671.
%K nonn
%O 1,4
%A _Jaroslav Krizek_, Dec 23 2018
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