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%I #14 Aug 10 2020 09:49:51
%S 1,1,1,1,5,5,5,5,1,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,
%T 10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,
%U 50,50,50,50,50,50,50,50,50,50,50,50,50,50,50,50,50,50,50
%N Value of initial digit of n in Roman numeral representation.
%H Nathaniel Johnston, <a href="/A093704/b093704.txt">Table of n, a(n) for n = 1..3999</a>
%H Stephanus Gibbs, <a href="http://www.softhawkway.com/rcalc.htm">Roman Numeral and Date Conversion</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/RomanNumerals.html">Roman Numerals</a>
%e n=42 == XLII -> X == a(42)=10.
%p A093704 := proc(n) return convert(convert(n,roman)[1],arabic): end: seq(A093704(n),n=1..100); # _Nathaniel Johnston_, May 18 2011
%t FromDigits[StringTake[IntegerString[Range[70],"Roman"],1],"Roman"] (* _Harvey P. Dale_, Oct 10 2012 *)
%Y Cf. A000030.
%K nonn,easy,base
%O 1,5
%A _Reinhard Zumkeller_, May 17 2004
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