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A135129
Numbers such that the digital sums in bases 3, 4, 5, 6 and 7 all are equal.
1
1, 2, 1388, 2170, 2171, 2830, 2831, 10390, 10391, 12792, 12793, 12794, 17110, 17111, 17290, 17291, 36312, 36313, 36314, 37814, 41532, 41533, 41534, 50892, 50893, 50894, 52216, 52217, 52395, 56652, 56653, 56654, 95354, 96432, 96433, 96434
OFFSET
1,2
LINKS
EXAMPLE
a(3)=1388, since ds_3(1388)=ds_4(1388)=ds_5(1388)=ds_6(1388)=ds_7(1388), where ds_x=digital sum base x.
MATHEMATICA
Select[Range[30000], Total[IntegerDigits[#, 3]] == Total[IntegerDigits[#, 4]] == Total[IntegerDigits[#, 5]] == Total[IntegerDigits[#, 6]] == Total[IntegerDigits[#, 7]] &] (* G. C. Greubel, Sep 28 2016 *)
Select[Range[100000], Length[Union[Table[Total[IntegerDigits[#, b]], {b, 3, 7}]]]==1&] (* Harvey P. Dale, Oct 25 2020 *)
KEYWORD
nonn,base
AUTHOR
Hieronymus Fischer, Dec 31 2007
STATUS
approved