login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A290148 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. 0
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, 62, 72, 82, 93, 3, 13, 23, 33, 43, 53, 63, 73, 83, 94, 4, 14, 24, 34, 44, 54, 64, 74, 84, 95, 5, 15, 25, 35, 45, 55, 65, 75, 85, 96, 6, 16, 26, 36, 46, 56, 66, 76, 86, 97, 7 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Take list of integers n >= 1, move right digit of each term to left end of next term.

LINKS

Table of n, a(n) for n=1..71.

FORMULA

a(n) = (n -1 mod 10)*10^A004216(n) + floor(n/10). # Robert Israel, Jul 21 2017

EXAMPLE

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.

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.

MAPLE

f:= n -> (n-1 mod 10) * 10^ilog10(n) + floor(n/10);

PROG

(PARI) a(n) = my(precd = (n-1)%10); if (n < 10, precd, eval(concat(Str(precd), Str(n\10))));

CROSSREFS

Cf. A004216, A032762.

Sequence in context: A331879 A098755 A028430 * A171717 A303369 A154701

Adjacent sequences:  A290145 A290146 A290147 * A290149 A290150 A290151

KEYWORD

nonn,base

AUTHOR

Michel Marcus, Jul 21 2017

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified January 23 07:56 EST 2022. Contains 350510 sequences. (Running on oeis4.)