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A238508
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Smallest number m such that 3^m contains a string of n consecutive decreasing integers in its decimal representation.
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0
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OFFSET
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1,2
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LINKS
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EXAMPLE
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5 is the smallest exponent such that 3^5 contains two consecutive decreasing integers (3^5 = 243).
13 is the smallest exponent such that 3^13 contains three consecutive decreasing integers (3^13 = 1594323).
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PROG
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(Python)
def StrDec(x):
..for n in range(10**5):
....count = 0
....i = 0
....string = str(3**n)
....if len(string) == x and x == 1:
......return n
....while i < len(string)-1:
......if int(string[i]) == int(string[i+1])-1:
........count += 1
........i += 1
......else:
........if count >= x-1:
..........return n
........else:
..........count = 0
..........i += 1
....if count >= x-1:
......return n
x = 1
while x < 15:
..print(StrDec(x))
..x += 1
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CROSSREFS
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KEYWORD
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nonn,base,fini,full
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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