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A125887 a(1) = 1, a(n) = smallest positive number b not among a(1)..a(n-1) and not a multiple of 10 such that the first digit of b = the last digit of a(n-1). 2
1, 11, 12, 21, 13, 31, 14, 41, 15, 51, 16, 61, 17, 71, 18, 81, 19, 91, 101, 102, 22, 23, 32, 24, 42, 25, 52, 26, 62, 27, 72, 28, 82, 29, 92, 201, 103, 33, 34, 43, 35, 53, 36, 63, 37, 73, 38, 83, 39, 93, 301, 104, 44, 45, 54, 46, 64, 47, 74, 48, 84, 49, 94, 401, 105, 55, 56, 65 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

A dyslexic person might have trouble distinguishing this sequence from A125886!

LINKS

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

PROG

(Haskell)

a125887 n = a125887_list !! (n-1)

a125887_list = 1 : f '1' (filter ((> 0) . (`mod` 10)) [11..]) where

   f d zs = y : f (last $ show y) (xs ++ ys) where

       (xs, y:ys) = span ((/= d) . head . show) zs

-- Reinhard Zumkeller, Jul 06 2011

CROSSREFS

Cf. A125886.

Cf. A000030, A010879.

Sequence in context: A121979 A109372 A066686 * A107478 A153146 A132359

Adjacent sequences:  A125884 A125885 A125886 * A125888 A125889 A125890

KEYWORD

base,nonn,look

AUTHOR

Zak Seidov, Dec 13 2006

STATUS

approved

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Last modified November 18 10:38 EST 2017. Contains 294887 sequences.