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A168005 Numbers n with property that first digit of 9*n = last digit of n. 1
21, 32, 43, 54, 65, 76, 87, 98, 109, 121, 131, 141, 151, 161, 171, 181, 191, 201, 211, 221, 232, 242, 252, 262, 272, 282, 292, 302, 312, 322, 332, 343, 353, 363, 373, 383, 393, 403, 413, 423, 433, 443, 454, 464, 474, 484, 494, 504, 514, 524, 534, 544, 554 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..1000

EXAMPLE

9*21=189, 9*32=288, 9*43=387, 9*54=486, etc.

MATHEMATICA

Reap[Do[If[IntegerDigits[n][[ -1]]==IntegerDigits[9*n][[1]], Sow[n]], {n, 1000}]][[2, 1]]

Select[Range[100], Last[IntegerDigits[#]] == First[IntegerDigits[9 #]] &] (* G. C. Greubel, Jul 03 2016 *)

CROSSREFS

Cf. A167994, A167996, A167997, A167998, A168000, A168001, A168004.

Sequence in context: A168001 A168004 A118866 * A118535 A127423 A319477

Adjacent sequences:  A168002 A168003 A168004 * A168006 A168007 A168008

KEYWORD

base,nonn

AUTHOR

Zak Seidov, Nov 16 2009

STATUS

approved

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Last modified April 17 09:29 EDT 2021. Contains 343064 sequences. (Running on oeis4.)