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A036786
Length of Roman notation for n < length of decimal representation.
6
10, 50, 100, 101, 105, 110, 150, 200, 400, 500, 501, 505, 510, 550, 600, 900, 1000, 1001, 1002, 1004, 1005, 1006, 1009, 1010, 1011, 1015, 1020, 1040, 1050, 1051, 1055, 1060, 1090, 1100, 1101, 1105, 1110, 1150, 1200, 1400, 1500, 1501, 1505, 1510, 1550
OFFSET
1,1
LINKS
Nathaniel Johnston, Table of n, a(n) for n = 1..55 (complete up to 3999)
FORMULA
A006968(a(n)) < A055642(a(n)). - Reinhard Zumkeller, Apr 20 2013
EXAMPLE
1000 = M is shorter in Roman numerals, so 1000 is in this sequence.
MAPLE
for n from 1 to 3999 do if(length(convert(n, roman)) < length(n))then printf("%d, ", n): fi: od: # Nathaniel Johnston, May 18 2011
MATHEMATICA
Select[Range[2000], StringLength[IntegerString[#, "Roman"]]<IntegerLength[ #]&] (* Harvey P. Dale, Feb 10 2015 *)
PROG
(Haskell)
a036786 n = a036786_list !! (n-1)
a036786_list = [x | x <- [1..], a006968 x < a055642 x]
-- Reinhard Zumkeller, Apr 20 2013
CROSSREFS
Sequence in context: A061861 A243226 A283237 * A085444 A102915 A153780
KEYWORD
nonn,nice,easy,base
AUTHOR
EXTENSIONS
Corrected by Larry Reeves (larryr(AT)acm.org), Sep 25 2000
STATUS
approved