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A319921 Underline the central digit of all terms: the underlined digits reconstruct the starting sequence. This is also true if one translates the sequence in French and underlines the central letter of each word: the underlined letters spell the (French) sequence again. This is the lexicographically earliest sequence of distinct terms. 2
331, 233, 10177, 224, 10314, 10323, 210, 203, 110, 10717, 84700, 420, 121, 340, 311, 206, 236, 10182, 10454, 112, 302, 99300, 10217, 10331, 10206, 212, 103, 326, 10033, 136, 216, 217, 305, 218, 10084, 270, 117, 470, 1008224, 43400, 170, 11000, 10024, 21400, 14201, 307, 410, 10210, 313, 332, 1004644, 10066, 10304, 32100, 10184, 122 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
By construction, all integers have here an odd number of digits and an odd number of letters in their French translation.
LINKS
Eric Angelini, Des suites inouïes, Maths étonnantes, Tangente, No. 189, juillet-août 2019, p. 29.
Nicolas Graner, Les grands nombres en français. This link explains why the authors didn't take into account the letters B, J, K, W and Y.
EXAMPLE
The sequence starts with 331, 233, 10177, 224, 10314, and the central (underlined) digits are 3,3,1,2,3,... which are precisely the digits starting the sequence itself; now the successive 5 unique central letters of the above 5 French terms are T, R, O, I, S and this spells the beginning of TROIS CENT TRENTE ET UN, the term a(1).
The first term diverging from A319718 is a(21) = [TROISC(E)NTDEUX, 302] as a(21) is the smallest integer > a(16) = [DEUXC(E)NTSIX, 206], both having a central (underlined) letter E.
CROSSREFS
Cf. A319718 (repeated terms are allowed, in contrast to this sequence)
Sequence in context: A140908 A256586 A319718 * A365596 A179400 A139657
KEYWORD
base,nonn,word
AUTHOR
STATUS
approved

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Last modified April 18 03:33 EDT 2024. Contains 371767 sequences. (Running on oeis4.)