OFFSET
1,1
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
EXAMPLE
Sum of proper square divisors of 5292: 1764 + 441 + 196 + 49 + 36 + 9 + 4 + 1 = 2500 = 50^2 is square number.
MATHEMATICA
f[p_, e_] := (p^(2*(1 + Floor[e/2])) - 1)/(p^2 - 1); A035316[1] = 1; A035316[n_] := Times @@ f @@@ FactorInteger[n]; sqQ[n_] := n>1 && IntegerQ[Sqrt[n]];
Select[Range[100000], sqQ[A035316[#] - If[IntegerQ[Sqrt[#]], #, 0]] &] (* Amiram Eldar, Aug 12 2023 *)
PROG
(PARI) {for(n=1, 10^5, k=sumdiv(n, d, d*issquare(d)*(d<n)); if(issquare(k)&&k>>1, print(n)))}
CROSSREFS
KEYWORD
nonn
AUTHOR
Antonio Roldán, Nov 26 2013
STATUS
approved