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A028980 Numbers n such that sum of divisors of n is palindromic. 5
1, 2, 3, 4, 5, 7, 43, 81, 96, 98, 130, 146, 162, 166, 201, 205, 208, 211, 221, 241, 244, 251, 271, 274, 281, 300, 314, 325, 333, 365, 388, 422, 433, 438, 443, 463, 489, 519, 559, 633, 685, 793, 803, 827, 857, 877, 887, 1376, 1419, 1505, 1548 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..51.

P. De Geest, World!Of Numbers

MAPLE

isA028980 := proc(n)

    isA002113(numtheory[sigma](n)) ;

end proc:

for n from 1 to 2000 do

    if isA028980(n) then

        printf("%d, ", n) ;

    end if;

end do: # R. J. Mathar, Sep 09 2015

MATHEMATICA

Select[Range[1550], Reverse[x=IntegerDigits[DivisorSigma[1, #]]]==x&] (* Jayanta Basu, Jun 05 2013 *)

CROSSREFS

Sequence in context: A276522 A135709 A263043 * A183108 A096841 A029963

Adjacent sequences:  A028977 A028978 A028979 * A028981 A028982 A028983

KEYWORD

nonn,base

AUTHOR

Patrick De Geest

STATUS

approved

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Last modified June 19 06:47 EDT 2019. Contains 324218 sequences. (Running on oeis4.)