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%I #10 Jul 30 2015 12:57:40
%S 390,391,392,393,394,395,396,397,398,399,890,891,892,893,894,895,896,
%T 897,898,899,1390,1391,1392,1393,1394,1395,1396,1397,1398,1399,1890,
%U 1891,1892,1893,1894,1895,1896,1897,1898,1899
%N Numbers with four C's in Roman numerals.
%C These will always have CCCXC in them.
%H <a href="/index/Rec#order_11">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,0,0,0,0,0,0,0,1,-1).
%e 390 = CCCXC; 890 = DCCCXC
%t Select[Range[2000],StringCount[RomanNumeral[#],"C"]==4&] (* or *) LinearRecurrence[{1,0,0,0,0,0,0,0,0,1,-1},{390,391,392,393,394,395,396,397,398,399,890},40] (* _Harvey P. Dale_, Jul 30 2015 *)
%o (PARI) lista() = {for (i=0, 9, for (j=0, 9, print1((390+j)+500*i, ", ");););} \\ _Michel Marcus_, May 14 2014
%K nonn,easy,less,base
%O 1,1
%A _J. Lowell_, May 06 2014