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%I #15 Apr 08 2024 05:07:00
%S 1,2,4,6,12,18,36,48,64,96,192,240,480,720,960,1200,2400,2880,5760,
%T 7200,9600,14400,28800,33600,40320,60480,69120,86400,172800,201600,
%U 403200,483840,645120,967680,1161216,1306368,2612736,3919104,5225472,5971968
%N Number of divisors of A104350(n).
%H Amiram Eldar, <a href="/A104352/b104352.txt">Table of n, a(n) for n = 1..1000</a>
%H Reinhard Zumkeller, <a href="/A104350/a104350.txt">Products of largest prime factors of numbers <= n</a>.
%F a(n) = A000005(A104350(n)).
%t DivisorSigma[0, FoldList[Times, Array[FactorInteger[#][[-1, 1]] &, 50]]] (* _Amiram Eldar_, Apr 08 2024 *)
%o (PARI) gpf(n) = {my(p = factor(n)[, 1]); p[#p];}
%o a(n) = numdiv(prod(k = 2, n, gpf(k))); \\ _Amiram Eldar_, Apr 08 2024
%Y Cf. A000005, A104350, A104353, A027423.
%K nonn,changed
%O 1,2
%A _Reinhard Zumkeller_, Mar 06 2005
%E Offset changed to 1 and a(1) prepended by _Amiram Eldar_, Apr 08 2024
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