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A305799 Dirichlet convolution of A078899 with itself.

%I A305799 #5 Jun 13 2018 09:11:56
%S A305799 1,2,2,5,2,6,2,10,7,6,2,16,2,6,8,18,2,20,2,16,8,6,2,34,11,6,20,16,2,
%T A305799 26,2,30,8,6,12,50,2,6,8,36,2,26,2,16,28,6,2,66,15,32,8,16,2,56,12,38,
%U A305799 8,6,2,68,2,6,30,47,12,26,2,16,8,38,2,104,2,6,38,16,16,26,2,74,47,6,2,70,12,6,8,38,2,88,16,16,8,6,12,118,2,42
%N A305799 Dirichlet convolution of A078899 with itself.
%H A305799 Antti Karttunen, <a href="/A305799/b305799.txt">Table of n, a(n) for n = 1..65537</a>
%F A305799 a(n) = Sum_{d|n} A078899(d)*A078899(n/d).
%o A305799 (PARI)
%o A305799 up_to = 65537;
%o A305799 ordinal_transform(invec) = { my(om = Map(), outvec = vector(length(invec)), pt); for(i=1, length(invec), if(mapisdefined(om,invec[i]), pt = mapget(om, invec[i]), pt = 0); outvec[i] = (1+pt); mapput(om,invec[i],(1+pt))); outvec; };
%o A305799 A006530(n) = if(n>1, vecmax(factor(n)[, 1]), 1);
%o A305799 v078899 = ordinal_transform(vector(up_to,n,A006530(n)));
%o A305799 A078899(n) = v078899[n];
%o A305799 A305799(n) = sumdiv(n,d,A078899(d)*A078899(n/d));
%Y A305799 Cf. A078899, A305797, A305798.
%K A305799 nonn
%O A305799 1,2
%A A305799 _Antti Karttunen_, Jun 13 2018