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%I #13 Jul 05 2016 02:48:30
%S 21,32,43,54,65,76,86,97,108,119,131,141,151,161,171,181,191,201,211,
%T 221,231,241,252,262,272,282,292,302,312,322,332,342,352,362,372,383,
%U 393,403,413,423,433,443,453,463,473,483,493,504,514,524,534,544,554
%N Numbers n with property that first digit of 8*n = last digit of n.
%H G. C. Greubel, <a href="/A168004/b168004.txt">Table of n, a(n) for n = 1..1000</a>
%F For 1 <= t <= 9, n = 10*s+t is in the sequence iff for some d>=1, t*(10^d-8)/80 <= s <= t*(10^d-8)/10 + (10^d-1)/80. For each d >= 3, there are 10^d/8 such m. - _Robert Israel_, Jul 04 2016
%F a(n) - a(n-1) can be 1 : 8*624 = 4992 and 8*625 = 5000. - _Altug Alkan_, Jul 04 2016
%e 8*21=168, 8*32=256, 8*43=344, 8*54=432, etc.
%p select(n -> floor(8*n/10^ilog10(8*n))=n mod 10, [$1..554]); # _Robert Israel_, Jul 04 2016
%t Reap[Do[If[IntegerDigits[n][[ -1]]==IntegerDigits[8*n][[1]],Sow[n]],{n,1000}]][[2,1]]
%t Select[Range[800],Last[IntegerDigits[#]]==First[IntegerDigits[8#]]&] (* _Harvey P. Dale_, Nov 03 2013 *)
%Y Cf. A167994, A167996, A167997, A167998, A168000, A168001.
%K base,nonn
%O 1,1
%A _Zak Seidov_, Nov 16 2009
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