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A361633
a(n) is the denominator of the median of the prime factors of n with repetition.
4
1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 2, 1, 2, 1, 2, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 2, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 2, 1, 2, 1, 2, 1, 1, 1
OFFSET
2,5
FORMULA
For p a prime, a(p^k) = 1.
a(n) = denominator((A079879(n) + A361725(n))/2).
EXAMPLE
a(12) = 1 since 12 = 2*2*3, and the median of the factors is equal to 2/1.
a(36) = 2 since 30 = 2*2*3*3, and the median of the factors is equal to 5/2.
MATHEMATICA
a[n_]:=Denominator[Median[Flatten[ Table[#[[1]], {#[[2]]}] & /@ FactorInteger[n]]]]; Array[a, 88, 2]
CROSSREFS
Cf. A001222, A027746, A079879, A323172, A361566, A361631 (without repetition), A361632 (numerator), A361725.
Sequence in context: A214575 A081418 A088951 * A186006 A236398 A107453
KEYWORD
nonn,frac
AUTHOR
Stefano Spezia, Mar 18 2023
EXTENSIONS
Example corrected by Peter Munn, Aug 04 2024
STATUS
approved