Numbers k such that sigma(core(k)) = tau(k) where core(k) is the squarefree part of k, tau(k) is the number of divisors of k, and sigma(k) is their sum.

A069827

Numbers k such that sigma(core(k)) = tau(k) where core(k) is the squarefree part of k, tau(k) is the number of divisors of k, and sigma(k) is their sum.

Terms

    a(0) =1a(1) =20a(2) =27a(3) =45a(4) =96a(5) =150a(6) =245a(7) =294a(8) =486a(9) =504a(10) =540a(11) =605a(12) =612a(13) =726a(14) =832a(15) =845a(16) =1014a(17) =1400a(18) =1445a(19) =1500a(20) =1700a(21) =1734a(22) =1805a(23) =2166a(24) =2645a(25) =3125a(26) =3168a(27) =3174a(28) =3332a(29) =3825

External references