OFFSET
1,1
COMMENTS
Subsequence of A370071 after reordering (as the sequence is not monotonic; e.g., a(2) > a(3) and a(8) > a(9)). Leading 0 digits are allowed in the perfect power. For example, a(4) = 610 since 016 = 2^4. (If leading 0 digits were not allowed, a(4) would be 160500643816367088.)
LINKS
Chai Wah Wu, Table of n, a(n) for n = 1..16
EXAMPLE
a(1) = 2 since 2 = 2^1.
a(2) = 144 since 144 = 12^2.
a(3) = 8 since 8 = 2^3.
a(4) = 610 since 016 = 2^4.
a(5) = 5358359254990966640871840 since 0735948608251696955804943 = 59343^5
a(6) = 68330027629092351019822533679447 since 00059398947526192142327360782336 = 62464^6.
PROG
(Python)
from itertools import count
from sympy import integer_nthroot
def A371588(n):
a, b = 1, 2
while True:
s = sorted(str(b))
l = len(s)
m = int(''.join(s[::-1]))
u = int(''.join(s))
for i in count(max(2, integer_nthroot(u, n)[0])):
if (k:=i**n) > m:
break
t = sorted(str(k))
if ['0']*(l-len(t))+t == s:
return b
break
a, b = b, a+b
CROSSREFS
KEYWORD
nonn,base,more
AUTHOR
Chai Wah Wu, Mar 28 2024
STATUS
approved