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

15, 23, 27, 55, 39, 39, 47, 51, 87, 43, 63, 71, 127, 63, 83, 55, 99, 67, 175, 107, 111, 63, 119, 123, 67, 95, 147, 79, 159, 99, 167, 79, 295, 87, 183, 135, 191, 203, 207, 367, 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

Offset: 1

Author

Antti Karttunen, May 23 2019

Keywords

• nonn

Links

• Antti Karttunen, Table of n, a(n) for n = 1..25000

Crossrefs

Cf. A034448, A034460, A228058, A325379, A325824.

Cf. also A325319, A325320.

Programs

PARI

up_to = 10000;
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));
A228058list(up_to) = { my(v=vector(up_to), k=0, n=0); while(kA228058(n), k++; v[k] = n)); (v); };
v228058 = A228058list(up_to);
A228058(n) = v228058[n]; \\ Antti Karttunen, May 23 2019
A034448(n) = { my(f=factorint(n)); prod(k=1, #f~, 1+(f[k, 1]^f[k, 2])); }; \\ After code in A034448
A034460(n) = (A034448(n) - n);
A325823(n) = A034460(A228058(n));

Formula

a(n) = A034460(A228058(n)).

a(n) = A325824(n) - A325379(n).