cp's OEIS Frontend

A363820 Moving the rightmost digit of a number to place it furthest to the left adds 9 to the number.

%I A363820 #20 Oct 22 2023 15:14:08
%S A363820 12,23,34,45,56,67,78,89,101,212,323,434,545,656,767,878,989,1101,
%T A363820 2212,3323,4434,5545,6656,7767,8878,9989,11101,22212,33323,44434,
%U A363820 55545,66656,77767,88878,99989,111101,222212,333323,444434,555545,666656,777767,888878,999989
%N A363820 Moving the rightmost digit of a number to place it furthest to the left adds 9 to the number.
%C A363820 All terms k are repdigit numbers minus 10. The sequence starts with 22 - 10 = 12. - _Andrew Howroyd_, Oct 22 2023
%H A363820 Andrew Howroyd, <a href="/A363820/b363820.txt">Table of n, a(n) for n = 1..1000</a>
%e A363820 a(1) = 12 plus 9 = 21; the rightmost 2 is now in front and 1 at the end;
%e A363820 a(2) = 23 plus 9 = 32; the rightmost 3 is now in front and 2 at the end;
%e A363820 a(3) = 34 plus 9 = 43; the rightmost 4 is now in front and 3 at the end;
%e A363820 a(4) = 45 plus 9 = 54; the rightmost 5 is now in front and 4 at the end;
%e A363820 ...
%e A363820 a(9) = 101 plus 9 = 110; the rightmost 1 is now in front and 0 at the end; etc.
%t A363820 Select[Range[10^6],FromDigits[RotateRight[IntegerDigits[#]]]-#==9 &] (* _Stefano Spezia_, Oct 18 2023 *)
%o A363820 (Python)
%o A363820 def ok(n): s = str(n); return int(s[-1]+s[:-1]) - n == 9
%o A363820 print([k for k in range(10**6) if ok(k)]) # _Michael S. Branicky_, Oct 18 2023
%o A363820 (PARI) a(n) = if(n > 0, (n%9 + 1)*(10^(n\9 + 2)-1)/9 - 10) \\ _Andrew Howroyd_, Oct 22 2023
%Y A363820 Cf. A010785 (repdigit numbers), A228157, A363823.
%K A363820 base,nonn
%O A363820 1,1
%A A363820 _Eric Angelini_, Oct 18 2023