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A246661
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Run Length Transform of swinging factorials (A056040).
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9
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1, 1, 1, 2, 1, 1, 2, 6, 1, 1, 1, 2, 2, 2, 6, 6, 1, 1, 1, 2, 1, 1, 2, 6, 2, 2, 2, 4, 6, 6, 6, 30, 1, 1, 1, 2, 1, 1, 2, 6, 1, 1, 1, 2, 2, 2, 6, 6, 2, 2, 2, 4, 2, 2, 4, 12, 6, 6, 6, 12, 6, 6, 30, 20, 1, 1, 1, 2, 1, 1, 2, 6, 1, 1, 1, 2, 2, 2, 6, 6, 1, 1, 1, 2, 1, 1
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OFFSET
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0,4
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COMMENTS
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For the definition of the Run Length Transform see A246595.
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LINKS
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FORMULA
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a(2^n-1) = n$ where n$ is the swinging factorial of n, A056040(n).
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MATHEMATICA
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f[n_] := n!/Quotient[n, 2]!^2; Table[Times @@ (f[Length[#]]&) /@ Select[ Split[ IntegerDigits[n, 2]], #[[1]] == 1&], {n, 0, 85}] (* Jean-François Alcover, Jul 11 2017 *)
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PROG
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A246661_list = lambda len: RLT(lambda n: factorial(n)/factorial(n//2)^2, len)
(Python)
from math import factorial
def A246661(n): return RLT(n, lambda m: factorial(m)//factorial(m//2)**2) # Chai Wah Wu, Feb 04 2022
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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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