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A305798 Dirichlet convolution of A078898 with itself.

%I A305798 #6 Jun 13 2018 09:12:05
%S A305798 1,2,2,5,2,8,2,12,5,12,2,22,2,16,8,28,2,28,2,34,10,24,2,56,5,28,14,46,
%T A305798 2,52,2,64,14,36,8,83,2,40,16,88,2,70,2,70,26,48,2,136,5,64,20,82,2,
%U A305798 94,10,120,22,60,2,164,2,64,34,144,12,106,2,106,26,100,2,220,2,76,36,118,8,124,2,216,42,84,2,224,14,88,32,184,2,192,10
%N A305798 Dirichlet convolution of A078898 with itself.
%H A305798 Antti Karttunen, <a href="/A305798/b305798.txt">Table of n, a(n) for n = 1..65537</a>
%F A305798 a(n) = Sum_{d|n} A078898(d)*A078898(n/d).
%o A305798 (PARI)
%o A305798 up_to = 65537;
%o A305798 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 A305798 A020639(n) = if(n>1, if(n>n=factor(n, 0)[1, 1], n, factor(n)[1, 1]), 1); \\ From A020639
%o A305798 v078898 = ordinal_transform(vector(up_to,n,A020639(n)));
%o A305798 A078898(n) = v078898[n];
%o A305798 A305798(n) = sumdiv(n,d,A078898(d)*A078898(n/d));
%Y A305798 Cf. A078898, A305791, A305796, A305797, A305799.
%K A305798 nonn
%O A305798 1,2
%A A305798 _Antti Karttunen_, Jun 13 2018