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A325913
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Integers m such that there are exactly two powers of 2 between 3^m and 3^(m+1).
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3
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1, 3, 5, 6, 8, 10, 11, 13, 15, 17, 18, 20, 22, 23, 25, 27, 29, 30, 32, 34, 35, 37, 39, 41, 42, 44, 46, 47, 49, 51, 52, 54, 56, 58, 59, 61, 63, 64, 66, 68, 70, 71, 73, 75, 76, 78, 80, 82, 83, 85, 87, 88, 90, 92, 94, 95, 97, 99, 100
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OFFSET
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1,2
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COMMENTS
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Also largest m such that 2^(m+n) > 3^m. - Bob Selcoe, Dec 19 2021
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LINKS
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FORMULA
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a(n) = floor(n/(log_2(3)-1)).
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EXAMPLE
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For m=3, there are exactly two powers of 2 between 3^3 = 27 and 3^(3+1) = 81: 32 and 64, since 27 < 32 < 64 < 81. Therefore, m=3 is an element of the sequence (at n=2).
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PROG
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(Python)
import math
def a(n):
return math.floor(n/(math.log2(3)-1))
for n in range(1, 101):
print("a(" + str(n) + ") = " + str(a(n)))
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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