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!)
A055263 a(n) = Sum of digits of (n + a(n-1)). 8
0, 1, 3, 6, 1, 6, 3, 1, 9, 9, 10, 3, 6, 10, 6, 3, 10, 9, 9, 10, 3, 6, 10, 6, 3, 10, 9, 9, 10, 12, 6, 10, 6, 12, 10, 9, 9, 10, 12, 6, 10, 6, 12, 10, 9, 9, 10, 12, 6, 10, 6, 12, 10, 9, 9, 10, 12, 15, 10, 15, 12, 10, 9, 9, 10, 12, 15, 10, 15, 12, 10, 9, 9, 10, 12, 15, 10, 15, 12, 10, 9, 9, 10 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
COMMENTS
If n=0 or 8 mod 9, then a(n)=0 mod 9; if n=1, 4 or 7 mod 9, then a(n)=1 mod 9; if n=2 or 6 mod 9, then a(n)=3 mod 9; if n=3 or 5 mod 9, then a(n)=6 mod 9.
LINKS
FORMULA
a(n) = A007953(A055262(n)) = A007953(n + a(n-1)).
EXAMPLE
a(13)=10 because a(12)=6, 13 + 6 = 19 and 1 + 9 = 10.
MATHEMATICA
nxt[{n_, a_}]:={n+1, Total[IntegerDigits[n+a+1]]}; Transpose[NestList[nxt, {0, 0}, 90]][[2]] (* Harvey P. Dale, Aug 11 2016 *)
CROSSREFS
Sequence in context: A355072 A134804 A145389 * A004157 A331514 A091068
KEYWORD
base,easy,nonn
AUTHOR
Henry Bottomley, May 08 2000
EXTENSIONS
More terms from Paolo P. Lava, Jul 31 2007
STATUS
approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 28 11:59 EDT 2024. Contains 371254 sequences. (Running on oeis4.)