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A098769 Abundant numbers whose reversal is also an abundant number. 2
24, 42, 48, 66, 84, 88, 204, 210, 216, 222, 228, 234, 240, 246, 252, 258, 264, 270, 272, 276, 282, 288, 294, 402, 408, 414, 420, 426, 432, 438, 444, 450, 456, 462, 464, 468, 474, 480, 486, 492, 498, 606, 612, 616, 618, 624, 630, 636, 642, 648, 650, 654, 660 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

EXAMPLE

a(1)=24 because 24 and the reversal of 24, i.e. 42, are abundant numbers.

MATHEMATICA

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 *)

CROSSREFS

Cf. A005101.

Sequence in context: A007372 A062910 A098900 * A162886 A274350 A063702

Adjacent sequences:  A098766 A098767 A098768 * A098770 A098771 A098772

KEYWORD

easy,nonn,base

AUTHOR

Shyam Sunder Gupta, Oct 02 2004

EXTENSIONS

Edited by N. J. A. Sloane, Apr 29 2007

STATUS

approved

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Last modified April 22 22:19 EDT 2021. Contains 343197 sequences. (Running on oeis4.)