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A113009
{Sum of the digits of n} raised to the power {number of digits of n}.
2
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 1, 4, 9, 16, 25, 36, 49, 64, 81, 100, 4, 9, 16, 25, 36, 49, 64, 81, 100, 121, 9, 16, 25, 36, 49, 64, 81, 100, 121, 144, 16, 25, 36, 49, 64, 81, 100, 121, 144, 169, 25, 36, 49, 64, 81, 100, 121, 144, 169, 196, 36, 49, 64, 81, 100, 121, 144, 169, 196
OFFSET
0,3
COMMENTS
Fixed points are: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 81, 5832. Are there any others?
Fixed points include: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 81, 512, 2401. There are no other fixed points less than 10^1000. - Chai Wah Wu, Feb 28 2019
FORMULA
a(ijk...)[m digits ijk...]=(i+j+k)^m
EXAMPLE
a(9)=9^1=9
a(19)=(1+9)^2=100
a(101)=(1+0+1)^3=8
MATHEMATICA
Join[{0}, Table[Total[IntegerDigits[n]]^IntegerLength[n], {n, 100}]] (* Harvey P. Dale, Nov 09 2014 *)
PROG
(Python)
def A113009(n):
return sum(int(d) for d in str(n))**len(str(n)) # Chai Wah Wu, Feb 28 2019
CROSSREFS
Cf. A101337.
Sequence in context: A325454 A112875 A113018 * A068064 A152147 A333830
KEYWORD
base,easy,nonn
AUTHOR
Alexandre Wajnberg, Jan 03 2006
STATUS
approved