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A080716 Numbers n such that sum of the divisors of n equals the sum of the reversals of the divisors of n. +0
1
1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 22, 30, 33, 42, 44, 55, 66, 77, 88, 99, 101, 121, 131, 151, 181, 191, 202, 242, 262, 303, 313, 330, 353, 363, 373, 383, 393, 404, 462, 484, 505, 606, 626, 681, 707, 727, 757, 772, 787, 797, 808, 824, 890, 909, 919, 929, 939, 989, 1111 (list; graph; listen)
OFFSET

1,2

EXAMPLE

Sum of divisors of 30: 1+2+3+5+6+10+15+30=72; sum of reversals of divisors of 30: 1+2+3+5+6+1+51+3=72. Therefore 30 belongs to the sequence.

MATHEMATICA

rev[n_] := FromDigits[Reverse[IntegerDigits[n]]]; Select[Range[10^4], Apply[Plus, Map[rev, Divisors[ # ]]] == DivisorSigma[1, # ] &]

CROSSREFS

Adjacent sequences: A080713 A080714 A080715 this_sequence A080717 A080718 A080719

Sequence in context: A039228 A062179 A122875 this_sequence A071242 A141033 A044959

KEYWORD

base,nonn

AUTHOR

Joseph L. Pe (joseph_l_pe(AT)hotmail.com), Mar 05 2003

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Last modified October 13 09:05 EDT 2008. Contains 145008 sequences.


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