

A074242


Numbers n such that sigma(n+1) = reverse(sigma(n)).


1




OFFSET

1,1


LINKS

Table of n, a(n) for n=1..4.


EXAMPLE

sigma(5602 + 1) = 6048 = reverse(8406) = reverse(sigma(5602)), so 5602 is a term of the sequence.


MATHEMATICA

Do[ If[FromDigits[Reverse[IntegerDigits[DivisorSigma[1, n]]]] == DivisorSigma[1, n + 1], Print[n]], {n, 1, 10^7}]


CROSSREFS

Sequence in context: A109565 A126784 A071813 * A032737 A237507 A198164
Adjacent sequences: A074239 A074240 A074241 * A074243 A074244 A074245


KEYWORD

base,more,nonn


AUTHOR

Joseph L. Pe, Sep 19 2002


EXTENSIONS

a(3)a(4) from Donovan Johnson, Feb 01 2009


STATUS

approved



