Let x be the sum of the divisors d_i of k such that d_i | sigma(k). Sequence lists the numbers k for which x^2 = sigma(k).

A284283

Let x be the sum of the divisors d_i of k such that d_i | sigma(k). Sequence lists the numbers k for which x^2 = sigma(k).

Terms

    a(0) =1a(1) =66a(2) =1092a(3) =1416a(4) =38280a(5) =38760a(6) =43080a(7) =92960a(8) =101024a(9) =112672a(10) =168210a(11) =175230a(12) =180090a(13) =194130a(14) =260400a(15) =491536a(16) =863772a(17) =891996a(18) =1004640a(19) =1061400a(20) =1234464a(21) =1282848a(22) =1294944a(23) =2010528a(24) =2041632a(25) =2079648a(26) =2090016a(27) =3394440a(28) =3653640a(29) =3673080

External references