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A291352
Numerators of the Collatz parity generator fractions.
0
1, 3, 7, 191, 25983, 2663063519, 7160414743310596607, 208229791652776621349215306687873023871, 45218742589363955614633859184750699518167124046103786511727246869388335095775
OFFSET
1,2
COMMENTS
a(n) is a numerator of a fraction of the form a(n)/(2^2^n + 1) whose expansion into a repeating binary string models the n-th parity in the Collatz orbit of an integer.
EXAMPLE
a(1)=1 => f(1) = 1/3 => b(1) = 101010...
a(2)=3 => f(2) = 3/5 => b(2) = 10011001...
elements in b(2) determine the parity of elements at index 2 in the Collatz parity sequence of an integer.
CROSSREFS
Cf. A006666.
Sequence in context: A114789 A128273 A105763 * A132564 A057619 A377402
KEYWORD
nonn
AUTHOR
John Laky, Aug 22 2017
STATUS
approved