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A171903 Numbers m such that m and m+1 have at least two identical neighboring digits in their decimal representations. 4
99, 110, 111, 112, 113, 114, 115, 116, 117, 118, 199, 220, 221, 222, 223, 224, 225, 226, 227, 228, 299, 330, 331, 332, 333, 334, 335, 336, 337, 338, 399, 440, 441, 442, 443, 444, 445, 446, 447, 448, 499, 550, 551, 552, 553, 554, 555, 556, 557, 558, 599, 660 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(n) + 1 = A171901(k) for some k;

A171902(a(n)) = 1.

LINKS

R. Zumkeller, Table of n, a(n) for n = 1..5000

FORMULA

A196368(a(n)) + A196368(a(n)+1) = 0. - Reinhard Zumkeller, Jan 31 2014

PROG

(Haskell)

import Data.List (elemIndices)

a171903 n = a171903_list !! (n-1)

a171903_list = elemIndices 0 $

               zipWith (+) a196368_list $ tail a196368_list

-- Reinhard Zumkeller, Jan 31 2014

CROSSREFS

Cf. A196368, A171901, A171904.

Sequence in context: A296881 A243259 A171904 * A072433 A133650 A045298

Adjacent sequences:  A171900 A171901 A171902 * A171904 A171905 A171906

KEYWORD

base,nonn,look

AUTHOR

Reinhard Zumkeller, Feb 07 2010

STATUS

approved

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Last modified February 26 09:05 EST 2020. Contains 332277 sequences. (Running on oeis4.)