OFFSET
1,1
COMMENTS
Unlike the case in A002963, C is counted as one stroke and D is counted as two strokes here. This sequence is complete up to 3999, though it may contain some more terms such as 5000 depending on the convention used to represent larger numbers. - Nathaniel Johnston, May 18 2011
FORMULA
Numbers that require three strokes when written in Roman numerals (excluding serifs).
CROSSREFS
KEYWORD
nonn,easy,fini,full,base
AUTHOR
Dylan Nicholson (wizofaus(AT)hotmail.com), May 11 2006
EXTENSIONS
a(12)-a(16) from Nathaniel Johnston, May 18 2011
STATUS
approved