|
%I #7 Oct 02 2013 15:47:23
%S 24,42,48,66,84,88,204,210,216,222,228,234,240,246,252,258,264,270,
%T 272,276,282,288,294,402,408,414,420,426,432,438,444,450,456,462,464,
%U 468,474,480,486,492,498,606,612,616,618,624,630,636,642,648,650,654,660
%N Abundant numbers whose reversal is also an abundant number.
%H Harvey P. Dale, <a href="/A098769/b098769.txt">Table of n, a(n) for n = 1..1000</a>
%e a(1)=24 because 24 and the reversal of 24, i.e. 42, are abundant numbers.
%t anrQ[n_]:=Module[{rn=FromDigits[Reverse[IntegerDigits[n]]]}, DivisorSigma[ 1,n]>2n&&DivisorSigma[1,rn]>2rn]; Select[Range[700],anrQ] (* _Harvey P. Dale_, Jun 27 2012 *)
%Y Cf. A005101.
%K easy,nonn,base
%O 1,1
%A _Shyam Sunder Gupta_, Oct 02 2004
%E Edited by _N. J. A. Sloane_, Apr 29 2007
|
