A142958 Roman numerals containing three letters (i.e., III, VII, XII, XIV, ...).

3, 7, 12, 14, 16, 19, 21, 25, 30, 41, 45, 52, 54, 56, 59, 61, 65, 70, 91, 95, 102, 104, 106, 109, 111, 115, 120, 140, 151, 155, 160, 190, 201, 205, 210, 250, 300, 401, 405, 410, 450, 502, 504, 506, 509, 511, 515, 520, 540, 551, 555, 560, 590, 601, 605, 610, 650

Offset: 1

Author

David Bodycombe (davidbod(AT)hotmail.com), Jul 12 2008

Keywords

• base
• easy
• nonn

Links

• Nathaniel Johnston, Table of n, a(n) for n = 1..93 (complete up to 3999)
• Ron Barnette's Zeno's Coffeehouse, Challenge #56 Result. Mentions this sequence.
• Gerard Schildberger, The first 3999 numbers in Roman numerals.

Crossrefs

Cf. A178968.

Programs

Maple

for n from 1 to 3999 do if(length(convert(n, roman)) = 3)then printf("%d, ", n): fi: od: # Nathaniel Johnston, May 18 2011

Mathematica

(* go to the hyperlink and assign the first 700 Roman numerals to the variable 'lst' so that lst = {I, II, III, ..., DCXCVIII, DCXCIX, DCC} and then *) Select[ Range[2, 1000], StringLength@ SymbolName@ lst[[ # ]] == 3 &] (* Robert G. Wilson v, Aug 12 2008 *)

Extensions

More terms from Robert G. Wilson v, Aug 12 2008