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A363820
Moving the rightmost digit of a number to place it furthest to the left adds 9 to the number.
2
12, 23, 34, 45, 56, 67, 78, 89, 101, 212, 323, 434, 545, 656, 767, 878, 989, 1101, 2212, 3323, 4434, 5545, 6656, 7767, 8878, 9989, 11101, 22212, 33323, 44434, 55545, 66656, 77767, 88878, 99989, 111101, 222212, 333323, 444434, 555545, 666656, 777767, 888878, 999989
OFFSET
1,1
COMMENTS
All terms k are repdigit numbers minus 10. The sequence starts with 22 - 10 = 12. - Andrew Howroyd, Oct 22 2023
LINKS
EXAMPLE
a(1) = 12 plus 9 = 21; the rightmost 2 is now in front and 1 at the end;
a(2) = 23 plus 9 = 32; the rightmost 3 is now in front and 2 at the end;
a(3) = 34 plus 9 = 43; the rightmost 4 is now in front and 3 at the end;
a(4) = 45 plus 9 = 54; the rightmost 5 is now in front and 4 at the end;
...
a(9) = 101 plus 9 = 110; the rightmost 1 is now in front and 0 at the end; etc.
MATHEMATICA
Select[Range[10^6], FromDigits[RotateRight[IntegerDigits[#]]]-#==9 &] (* Stefano Spezia, Oct 18 2023 *)
PROG
(Python)
def ok(n): s = str(n); return int(s[-1]+s[:-1]) - n == 9
print([k for k in range(10**6) if ok(k)]) # Michael S. Branicky, Oct 18 2023
(PARI) a(n) = if(n > 0, (n%9 + 1)*(10^(n\9 + 2)-1)/9 - 10) \\ Andrew Howroyd, Oct 22 2023
CROSSREFS
Cf. A010785 (repdigit numbers), A228157, A363823.
Sequence in context: A004960 A098953 A228157 * A072485 A035333 A001704
KEYWORD
base,nonn
AUTHOR
Eric Angelini, Oct 18 2023
STATUS
approved