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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

Table of n, a(n) for n=1..55.

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 March 21 12:09 EDT 2019. Contains 321369 sequences. (Running on oeis4.)