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A121993 Numbers n that yield a smaller number a(n) under the "Look and Say" function A045918. 2
33, 44, 55, 66, 77, 88, 99, 111, 222, 333, 444, 555, 666, 777, 888, 999, 1111, 1222, 1333, 1444, 1555, 1666, 1777, 1888, 1999, 2000, 2111, 2222, 2233, 2244, 2255, 2266, 2277, 2288, 2299, 2333, 2444, 2555, 2666, 2777, 2888, 2999, 3000, 3111, 3222, 3300 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Eric Weisstein's World of Mathematics, Look and Say Sequence.

EXAMPLE

E.g. a(26)=2000 because under the Look and Say operator, 2000 is described as one two three zeros or: 1230, which is smaller than 2000.

PROG

(Haskell)

a121993 n = a121993_list !! (n-1)

a121993_list = filter (\x -> a045918 x < x) [0..]

-- Reinhard Zumkeller, Jan 25 2014

CROSSREFS

Cf. A045918, A005150, A005341, A023989, A079475.

Sequence in context: A046041 A140151 A196579 * A225565 A050875 A060876

Adjacent sequences:  A121990 A121991 A121992 * A121994 A121995 A121996

KEYWORD

easy,nonn,base

AUTHOR

Sergio Pimentel, Sep 11 2006

STATUS

approved

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Last modified June 2 17:02 EDT 2020. Contains 334787 sequences. (Running on oeis4.)