Integers k such that there exists an integer 0<m<k such that sigma(m)^2 + sigma(k)^2 = 2*(m^2+k^2).

A384255

Integers k such that there exists an integer 0<m<k such that sigma(m)^2 + sigma(k)^2 = 2*(m^2+k^2).

Terms

    a(0) =2a(1) =21a(2) =27a(3) =123a(4) =175a(5) =2133a(6) =2187a(7) =6093a(8) =340917a(9) =504309a(10) =1594323a(11) =1895841a(12) =5308415a(13) =23006577a(14) =62188641

External references