Narcissistic decimal number
A Narcissistic decimal number is a positice decimal number, in which if there are digits in the number then the sum of all the individual digits of the number raised to the power is equal to .
For example, if is 153 then , the number of digits is 3 and we have and so 153 is a narcissistic decimal number.
The task is to generate and show here, the first 25 narcissistic numbers.
Perl 6
Here is a straightforward, naive implementation. Should work but takes ages. <lang perl6>sub is-narcissic(Int $n) { $n == [+] $n.comb »**» $n.chars }
say (grep &is-narcissic, 0 .. *)[^25];</lang>
Python
This solution pre-computes the powers once.
<lang python>from __future__ import print_function from itertools import count, islice
def narcissists():
for digits in count(0): digitpowers = [i**digits for i in range(10)] for n in range(int(10**(digits-1)), 10**digits): div, digitpsum = n, 0 while div: div, mod = divmod(div, 10) digitpsum += digitpowers[mod] if n == digitpsum: yield n
for i, n in enumerate(islice(narcissists(), 25), 1):
print(n, end=' ') if i % 5 == 0: print()
print()</lang>
- Output:
0 1 2 3 4 5 6 7 8 9 153 370 371 407 1634 8208 9474 54748 92727 93084 548834 1741725 4210818 9800817 9926315