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A135111
Numbers such that the digital sum base 2 and the digital sum base 3 are in a ratio of 2:3.
1
5, 33, 78, 106, 116, 142, 150, 154, 156, 170, 178, 184, 202, 204, 210, 215, 226, 228, 278, 284, 294, 308, 312, 332, 338, 340, 344, 356, 377, 390, 396, 418, 420, 424, 450, 455, 467, 473, 483, 513, 526, 534, 550, 582, 586, 588, 596, 600, 612, 619, 624, 629
OFFSET
1,1
LINKS
EXAMPLE
a(1)=5, since ds_2(5):ds_3(5)=2:3.
MAPLE
select(t -> convert(convert(t, base, 3), `+`)/convert(convert(t, base, 2), `+`) = 3/2, [$1..1000]); # Robert Israel, Sep 26 2016
MATHEMATICA
Select[Range[500], 3*Total[IntegerDigits[#, 2]] == 2*Total[IntegerDigits[#, 3]] &] (* G. C. Greubel, Sep 26 2016 *)
PROG
(PARI) isok(n) = 2*vecsum(digits(n, 3)) == 3*vecsum(digits(n, 2)); \\ Michel Marcus, Sep 26 2016
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Hieronymus Fischer, Dec 24 2007
STATUS
approved