1,2

Table of n, a(n) for n=1..9.

2^18 is the first power of 2 to contain 2 twice. So a(2) = 18.

3^21 is the first power of 3 to contain 3 three times. So a(3) = 21.

(Python)

def tes(n):

..for k in range(1, 10**3):

....if(str(n**k).count(str(n)) == n:

......return k

n = 1

while n < 10:

..print(tes(n), end=', ')

..n += 1

Sequence in context: A001101 A088341 A105145 * A120416 A293751 A090891

Adjacent sequences: A244600 A244601 A244602 * A244604 A244605 A244606

nonn,base,fini,full

Derek Orr, Jul 01 2014

approved