Solutions to 2*x - phi(x) = sigma(x)/2, where phi(x) is the Euler totient function of x.

A290704

Solutions to 2*x - phi(x) = sigma(x)/2, where phi(x) is the Euler totient function of x.

Terms

    a(0) =1680a(1) =4200a(2) =27000a(3) =175392a(4) =282960a(5) =707400a(6) =1668480a(7) =3344544a(8) =5658480a(9) =14146200a(10) =48644064a(11) =90008880a(12) =130110624a(13) =225022200a(14) =357994728a(15) =460763160a(16) =607281696a(17) =1926458352a(18) =3830537880a(19) =5857651296a(20) =7840881216a(21) =8414628480a(22) =8704032876a(23) =8843224500a(24) =14279194512a(25) =29522053080

External references