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A371589
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Smallest number m > 1 such that some permutation of the digits of m^n is a Fibonacci number.
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1
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2, 12, 2, 19002, 433153, 472133, 10064513, 61054259, 67878079, 8152101, 46077414, 11395185, 28556455, 11730986, 179311318, 1542839498, 443163383, 2426412518, 433059953, 443302473, 2654438078, 2764480203, 5945916934
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OFFSET
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1,1
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COMMENTS
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Unlike in A370071 or A371588, no leading 0's are allowed in m^n or the Fibonacci number.
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LINKS
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EXAMPLE
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a(4) = 19002 since 19002^4 = 130375880664608016 and a permutation of its digits results in 160500643816367088, a Fibonacci number.
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PROG
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(Python)
from itertools import count
from sympy import integer_nthroot
a, b = 1, 2
while True:
s = sorted(str(b))
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 t == s:
return i
break
a, b = b, a+b
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CROSSREFS
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KEYWORD
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nonn,base,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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