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A114261
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Numbers k such that the 5th power of k contains exactly 5 copies of each digit of k.
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6
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961527834, 7351062489, 8105632794, 8401253976, 8731945026, 9164072385, 9238750614, 9615278340, 9847103256, 72308154699, 73510624890, 81056327940, 83170652949, 83792140506, 84012539760, 87319450260, 91602408573, 91640723850, 92387506140, 96152783400, 98471032560
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OFFSET
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1,1
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COMMENTS
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Some of the early terms of the sequence are also pandigital, i.e. they contain all the 10 digits once. This is probably accidental, but quite curious!
All terms are divisible by 9. First decimal digit of a term is 6 or larger. - Chai Wah Wu, Feb 27 2024
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LINKS
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EXAMPLE
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E.g. 961527834 is in the sequence since its 5th power 821881685441327565743977956591832631269739424 contains five 9's, five 6's, five 1's and so on.
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PROG
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(Python)
from itertools import count, islice
from sympy import integer_nthroot
def A114261_gen(): # generator of terms
for l in count(1):
a = integer_nthroot(10**(5*l-1), 5)[0]
if (a9:=a%9):
a += 9-a9
for b in range(a, 10**l, 9):
if sorted(str(b)*5)==sorted(str(b**5)):
yield b
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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