A118098 Numbers that require three strokes when written in Roman numerals (excluding serifs). III IV VI IX XI LI XC CII CV CX CL.

3, 4, 6, 9, 11, 51, 90, 102, 105, 110, 150, 201, 300, 400, 501, 600

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

Links

Table of n, a(n) for n=1..16.

Formula

Numbers that require three strokes when written in Roman numerals (excluding serifs).

Crossrefs

Sequence in context: A301654 A289233 A039889 * A367477 A022297 A010430

Adjacent sequences: A118095 A118096 A118097 * A118099 A118100 A118101

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