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 A094109 Start with "I" in Roman numerals (one). The next number (in Roman numerals) describes the number of Roman numerals written previously in the sequence. Convert this infinite sequence into an infinite sequence of Arabic numbers. 1
 1, 1, 2, 4, 6, 8, 12, 15, 17, 21, 24, 28, 34, 39, 44, 48, 54, 57, 61, 64, 68, 74, 79, 84, 90, 92, 96, 100, 101, 103, 107, 111, 114, 118, 124, 129, 134, 140, 143, 149, 154, 158, 164, 169, 174, 180, 185, 191, 195, 199, 204, 208, 214, 219, 224, 230, 235, 241 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS Nathaniel Johnston, Table of n, a(n) for n = 1..573 FORMULA a(n) = a(n-1) + A006968(a(n-1)) for n >= 3. - Nathaniel Johnston, May 18 2011 EXAMPLE The sequence begins I, I, II, IV, VI, VIII, XII, XV, XVII, XXI, XXIV, XXVIII, XXXIV, XXIX, XLIII, XLVIII, LIV, LVII, LXI, LXIV, ... MAPLE A094109 := proc(n) option remember: if(n<=2)then return 1:fi: return procname(n-1) + length(convert(procname(n-1), roman)): end: seq(A094109(n), n=1..58); # Nathaniel Johnston, May 18 2011 CROSSREFS See A006968 for how to spell the Roman numerals. Sequence in context: A131197 A078327 A214415 * A090404 A015937 A058825 Adjacent sequences:  A094106 A094107 A094108 * A094110 A094111 A094112 KEYWORD nonn,base AUTHOR Eric Angelini, May 03 2004 EXTENSIONS Extended by Nathaniel Johnston, May 18 2011 STATUS approved

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Last modified December 5 22:37 EST 2019. Contains 329782 sequences. (Running on oeis4.)