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%I #12 Jul 22 2017 09:16:54
%S 0,1,2,3,4,5,6,7,8,91,1,11,21,31,41,51,61,71,81,92,2,12,22,32,42,52,
%T 62,72,82,93,3,13,23,33,43,53,63,73,83,94,4,14,24,34,44,54,64,74,84,
%U 95,5,15,25,35,45,55,65,75,85,96,6,16,26,36,46,56,66,76,86,97,7
%N a(n) is the integer resulting from the concatenation of the unit digit of n-1 to the digits of n without its own unit digit.
%C Take list of integers n >= 1, move right digit of each term to left end of next term.
%F a(n) = (n -1 mod 10)*10^A004216(n) + floor(n/10). # _Robert Israel_, Jul 21 2017
%e For n=46, n-1 is 45, so a(46) is the concatenation of 5 (the unit digit of 45) and 4 (46 without 6), giving 54.
%e For n=123, n-1 is 122, so a(123) is the concatenation of 2 (the unit digit of 122) and 12 (123 without 3), giving 212.
%p f:= n -> (n-1 mod 10) * 10^ilog10(n) + floor(n/10);
%o (PARI) a(n) = my(precd = (n-1)%10); if (n < 10, precd, eval(concat(Str(precd), Str(n\10))));
%Y Cf. A004216, A032762.
%K nonn,base
%O 1,3
%A _Michel Marcus_, Jul 21 2017
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