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A325823 Sum of unitary proper divisors of A228058(n): a(n) = A034460(A228058(n)).

%I A325823 #10 May 28 2019 19:35:42
%S A325823 15,23,27,55,39,39,47,51,87,43,63,71,127,63,83,55,99,67,175,107,111,
%T A325823 63,119,123,67,95,147,79,159,99,167,79,295,87,183,135,191,203,207,367,
%U A325823 87,99,91,139,239,243,251,795,115,267,111,279,123,287,127,291,103,303,535,135,323,139,327,187,715,111,119,347,359,363,123,383
%N A325823 Sum of unitary proper divisors of A228058(n): a(n) = A034460(A228058(n)).
%H A325823 Antti Karttunen, <a href="/A325823/b325823.txt">Table of n, a(n) for n = 1..25000</a>
%F A325823 a(n) = A034460(A228058(n)).
%F A325823 a(n) = A325824(n) - A325379(n).
%o A325823 (PARI)
%o A325823 up_to = 10000;
%o A325823 isA228058(n) = if(!(n%2)||(omega(n)<2),0,my(f=factor(n),y=0); for(i=1,#f~,if(1==(f[i,2]%4), if((1==y)||(1!=(f[i,1]%4)),return(0),y=1), if(f[i,2]%2, return(0)))); (y));
%o A325823 A228058list(up_to) = { my(v=vector(up_to), k=0, n=0); while(k<up_to, n++; if(isA228058(n), k++; v[k] = n)); (v); };
%o A325823 v228058 = A228058list(up_to);
%o A325823 A228058(n) = v228058[n]; \\ _Antti Karttunen_, May 23 2019
%o A325823 A034448(n) = { my(f=factorint(n)); prod(k=1, #f~, 1+(f[k, 1]^f[k, 2])); }; \\ After code in A034448
%o A325823 A034460(n) = (A034448(n) - n);
%o A325823 A325823(n) = A034460(A228058(n));
%Y A325823 Cf. A034448, A034460, A228058, A325379, A325824.
%Y A325823 Cf. also A325319, A325320.
%K A325823 nonn
%O A325823 1,1
%A A325823 _Antti Karttunen_, May 23 2019