Define the array k(n,x) = number of m such that tau(gcd(n,m)) is x where m runs from 1 to n. Also define h(n,x) = Sum_{d|n : tau(d) = x} d. The sequence contains numbers n such that k(n,x)*x = h(n,x) has at least one solution x.

A197099

Define the array k(n,x) = number of m such that tau(gcd(n,m)) is x where m runs from 1 to n. Also define h(n,x) = Sum_{d|n : tau(d) = x} d. The sequence contains numbers n such that k(n,x)*x = h(n,x) has at least one solution x.

Terms

    a(0) =1a(1) =2a(2) =4a(3) =32a(4) =48a(5) =180a(6) =189a(7) =224a(8) =288a(9) =360a(10) =432a(11) =1280a(12) =1344a(13) =1536a(14) =1600a(15) =4096a(16) =28672a(17) =46656a(18) =54000a(19) =108000a(20) =131220a(21) =150528a(22) =225792a(23) =262440a(24) =405450a(25) =442800a(26) =525312a(27) =532480a(28) =590400a(29) =594000

External references