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A168005

Numbers n with property that first digit of 9*n = last digit of n.

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.