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A168001 Numbers n with property that first digit of 7*n = last digit of n. 3
21, 32, 42, 43, 53, 64, 75, 85, 86, 96, 107, 118, 128, 129, 139, 151, 161, 171, 181, 191, 201, 211, 221, 231, 241, 251, 261, 271, 281, 292, 302, 312, 322, 332, 342, 352, 362, 372, 382, 392, 402, 412, 422, 433, 443, 453, 463, 473, 483, 493, 503, 513, 523, 533 (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

7*21=147, 7*32=224, 7*42=294, 7*43=301, etc.

MATHEMATICA

Reap[Do[If[IntegerDigits[n][[ -1]]==IntegerDigits[7*n][[1]], Sow[n]], {n, 1000}]][[2, 1]]

Select[Range[100], Last[IntegerDigits[#]] == First[IntegerDigits[7 #]] &] (* G. C. Greubel, Jul 03 2016 *)

CROSSREFS

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

Sequence in context: A002639 A054282 A095994 * A168004 A118866 A168005

Adjacent sequences:  A167998 A167999 A168000 * A168002 A168003 A168004

KEYWORD

base,nonn

AUTHOR

Zak Seidov, Nov 16 2009

STATUS

approved

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Last modified October 19 22:55 EDT 2019. Contains 328244 sequences. (Running on oeis4.)