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A167368
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a(n) = sigma((n!!)!).
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2
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OFFSET
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0,3
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LINKS
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Table of n, a(n) for n=0..6.
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FORMULA
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a(n) = A000203(A161563(n)).
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MATHEMATICA
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Array[DivisorSigma[1, #!!! ]&, 7, 1]
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PROG
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(PARI) A167368(n)=sigma( prod(k=0, n\2-1, n-2*k) ! ) \\ M. F. Hasler, Feb 07 2011
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CROSSREFS
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Cf. A062569, A167367.
Sequence in context: A169815 A239891 A226129 * A318165 A215240 A068697
Adjacent sequences: A167365 A167366 A167367 * A167369 A167370 A167371
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KEYWORD
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nonn,less
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AUTHOR
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Vladimir Joseph Stephan Orlovsky, Nov 01 2009
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EXTENSIONS
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a(0)=1 prepended by Alois P. Heinz, Jan 12 2022
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STATUS
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approved
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