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 A131998 Numbers n such that the number of letters in the n-th ordinal number divides n. 0
 5, 7, 10, 24, 33, 40, 44, 70, 78, 84, 90, 99, 105, 126, 132, 168, 176, 189, 190, 198, 208, 210, 231, 252, 306, 315, 340, 360, 368, 384, 391, 408, 420, 441, 462, 480, 520, 546, 575, 580, 598, 600, 608, 612, 638, 682, 693, 700, 702, 736, 740, 760, 770, 792, 814 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Which numbers k occur as the dividends? k...smallest n such that A006944(n)/n = k. 1...5. 2..10. 3..11 4..44. 5..never? 6..78. 7..70. 8.168. 9.189. 10.90. 11.99. LINKS FORMULA {n such that A006944(n)|n}. EXAMPLE a(1) = 5 because "fifth" has 5 letters. a(2) = 7 because "seventh" has 7 letters. a(3) = 10 because "tenth" has 5 letters and 10/5 = 2. a(4) = 24 because "twentyfourth" has 12 letters and 24/12 = 2. a(5) = 33 because "thirtythird" has 11 letters and 33/11 = 3. a(6) = 44 because "fortyfourth" has 11 letters and 44/11 = 4. CROSSREFS Cf. A006944, A116910. Sequence in context: A320447 A113194 A088768 * A141443 A215660 A015849 Adjacent sequences:  A131995 A131996 A131997 * A131999 A132000 A132001 KEYWORD easy,nonn,word AUTHOR Jonathan Vos Post, Oct 08 2007 EXTENSIONS Corrected and extended by R. J. Mathar, Oct 24 2007 STATUS approved

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Last modified October 15 20:04 EDT 2019. Contains 328037 sequences. (Running on oeis4.)