OFFSET
1,2
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
EXAMPLE
128 + sigma(128) = 128 + 255 = 383.
MATHEMATICA
Select[Range[1600], PalindromeQ[#+DivisorSigma[1, #]]&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, May 29 2017 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Giovanni Resta, Feb 06 2006
STATUS
approved