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A320009 a(0) = 1; for n > 0, a(n) = A000005(n) * a(n-A000005(n)), where A000005(n) gives the number of divisors of n.

%I A320009 #9 Nov 26 2018 17:13:28
%S A320009 1,1,2,2,3,4,8,8,12,24,32,48,48,96,128,192,240,384,288,768,768,1536,
%T A320009 1152,3072,1920,3456,4608,12288,6912,24576,9216,49152,27648,98304,
%U A320009 36864,196608,110592,393216,147456,786432,221184,1572864,294912,3145728,884736,4718592,1179648,9437184,1474560,3538944,5308416,37748736,7077888,75497472
%N A320009 a(0) = 1; for n > 0, a(n) = A000005(n) * a(n-A000005(n)), where A000005(n) gives the number of divisors of n.
%H A320009 Antti Karttunen, <a href="/A320009/b320009.txt">Table of n, a(n) for n = 0..150</a>
%F A320009 a(0) = 1; for n > 0, a(n) = A000005(n) * a(n-A000005(n)).
%t A320009 Nest[Append[#1, #2 #1[[-#2]] ] & @@ {#, DivisorSigma[0, Length@ #]} &, {1}, 53] (* _Michael De Vlieger_, Nov 25 2018 *)
%o A320009 (PARI) A320009(n) = if(0==n,1,numdiv(n)*A320009(n-numdiv(n)));
%Y A320009 Cf. A000005, A049820, A259934.
%Y A320009 Cf. also A320002, A320008, A320016.
%K A320009 nonn
%O A320009 0,3
%A A320009 _Antti Karttunen_, Nov 24 2018