A114927 Numbers n such that sigma(n)=3*reversal(n).

41, 291552, 692133, 2946762, 8231796, 21732508611, 27892659612

Offset: 1

Author

Farideh Firoozbakht, Jan 28 2006

Keywords

• base
• more
• nonn

Comments

No more terms through 10^9. - Ryan Propper, Jan 08 2007

a(8) > 10^12. - Giovanni Resta, Oct 28 2012

Crossrefs

Cf. A069216, A105324, A114928.

Programs

Mathematica

Do[If[DivisorSigma[1, n] == 3*FromDigits[Reverse[IntegerDigits[n]]], Print[n]], {n, 20000000}]

Extensions

a(6)-a(7) from Donovan Johnson, Dec 21 2008