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A223090
Numbers n with the property that if the base-8 representation of n is read backwards, the result is an integral multiple of n.
0
21, 189, 525, 567, 1134, 1365, 1533, 4599, 4725, 9198, 10773, 12285, 34125, 36855, 38325, 73710, 86037, 87381, 96957, 98301, 269325, 294903, 307125, 589806, 688149, 700245, 774333, 786429, 2150925, 2184525, 2322999, 2359287, 2423925, 2457525, 4645998, 4718574, 5505045, 5515797, 5592405, 5603157, 6193341, 6204093, 6280701, 6291453
OFFSET
1,1
COMMENTS
A217742 is a subsequence.
The multiples that occur are 2, 3, 5, 7 (cf. A222817-A222820).
EXAMPLE
n = 525 (base 10) = 1015 (base 8). Reading this backwards we get 5101 (base 8) = 2625 (base 10) = 5*n, so 525 is in the sequence.
MATHEMATICA
b8rQ[n_]:=Module[{c=FromDigits[Reverse[IntegerDigits[n, 8]], 8]}, c/n>1 && IntegerQ[c/n]]; Select[Range[63*10^5], b8rQ] (* Harvey P. Dale, Sep 18 2016 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
N. J. A. Sloane, Mar 23 2013
STATUS
approved