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A360574
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Binary expansions of odd numbers with three zeros in their binary expansion.
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1
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10001, 100011, 100101, 101001, 110001, 1000111, 1001011, 1001101, 1010011, 1010101, 1011001, 1100011, 1100101, 1101001, 1110001, 10001111, 10010111, 10011011, 10011101, 10100111, 10101011, 10101101, 10110011, 10110101, 10111001, 11000111, 11001011, 11001101, 11010011, 11010101, 11011001, 11100011
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OFFSET
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1,1
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COMMENTS
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For m >= 5, there are A000292(m-4) terms with m digits.
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LINKS
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FORMULA
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EXAMPLE
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1010101 has three digits 0 and is the binary expansion of the odd integer 85, so 1010101 is a term.
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MATHEMATICA
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FromDigits[IntegerDigits[#, 2]] & /@ Select[Range[1, 250, 2], DigitCount[#, 2, 0] == 3 &] (* Amiram Eldar, Feb 18 2023 *)
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PROG
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(Python)
from itertools import count, islice
from sympy.utilities.iterables import multiset_permutations
def A360574_gen(): # generator of terms
yield from (int('1'+''.join(d)+'1') for l in count(0) for d in multiset_permutations('000'+'1'*l))
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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