A118880 a(n) is the cube of the sum of digits of n.

0, 1, 8, 27, 64, 125, 216, 343, 512, 729, 1, 8, 27, 64, 125, 216, 343, 512, 729, 1000, 8, 27, 64, 125, 216, 343, 512, 729, 1000, 1331, 27, 64, 125, 216, 343, 512, 729, 1000, 1331, 1728, 64, 125, 216, 343, 512, 729, 1000, 1331, 1728, 2197, 125, 216, 343, 512

Offset

0,3

Links

Table of n, a(n) for n=0..53.

Formula

a(n) = (A007953(n))^3. - R. J. Mathar, Apr 22 2010

Example

Trajectories of x->a(x), see A182128:
1 ->1 ->1 ->1 ->1 ->1 ->1 ->1 ->1 ->...
2 ->8 ->512 ->512 ->512 ->512 ->512 ->512 ->512 ->...
3 ->27 ->729 ->5832 ->5832 ->5832 ->5832 ->5832 ->5832 ->...
4 ->64 ->1000 ->1 ->1 ->1 ->1 ->1 ->1 ->...
5 ->125 ->512 ->512 ->512 ->512 ->512 ->512 ->512 ->...
6 ->216 ->729 ->5832 ->5832 ->5832 ->5832 ->5832 ->5832 ->...
7 ->343 ->1000 ->1 ->1 ->1 ->1 ->1 ->1 ->...
8 ->512 ->512 ->512 ->512 ->512 ->512 ->512 ->512 ->...
9 ->729 ->5832 ->5832 ->5832 ->5832 ->5832 ->5832 ->5832 ->...
10 ->1 ->1 ->1 ->1 ->1 ->1 ->1 ->1 ->...
11 ->8 ->512 ->512 ->512 ->512 ->512 ->512 ->512 ->...
12 ->27 ->729 ->5832 ->5832 ->5832 ->5832 ->5832 ->5832 ->...
13 ->64 ->1000 ->1 ->1 ->1 ->1 ->1 ->1 ->...
14 ->125 ->512 ->512 ->512 ->512 ->512 ->512 ->512 ->...
- R. J. Mathar, Jul 08 2012

Prog

(Python)
def a(n): return sum(map(int, str(n)))**3
print([a(n) for n in range(54)]) # Michael S. Branicky, Dec 26 2021

Crossrefs

Sequence in context: A352172 A055012 A069939 * A048390 A000578 A062292

Adjacent sequences: A118877 A118878 A118879 * A118881 A118882 A118883

Keyword

base,easy,nonn

Author

Giovanni Teofilatto, May 25 2006

Extensions

Name and offset corrected by Jon E. Schoenfield, Dec 26 2021

Status

approved