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

A037197

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

Terms

    a(0) =1a(1) =2a(2) =8a(3) =12a(4) =32a(5) =52a(6) =75a(7) =84a(8) =90a(9) =98a(10) =128a(11) =150a(12) =156a(13) =338a(14) =360a(15) =392a(16) =525a(17) =528a(18) =560a(19) =600a(20) =722a(21) =867a(22) =912a(23) =972a(24) =1050a(25) =1352a(26) =1452a(27) =1456a(28) =1525a(29) =1734

External references