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A158572 a(n) = A007814((2n-1)!! - 1). 1
1, 1, 3, 4, 1, 1, 4, 5, 1, 1, 3, 4, 1, 1, 5, 6, 1, 1, 3, 4, 1, 1, 4, 5, 1, 1, 3, 4, 1, 1, 6, 7, 1, 1, 3, 4, 1, 1, 4, 5, 1, 1, 3, 4, 1, 1, 5, 6, 1, 1, 3, 4, 1, 1, 4, 5, 1, 1, 3, 4, 1, 1, 7, 8, 1, 1, 3, 4, 1, 1, 4, 5, 1, 1, 3, 4, 1, 1, 5, 6, 1, 1, 3, 4, 1, 1, 4 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,3

COMMENTS

In contrast to A158570, it is a non-periodic and unlimited sequence.

LINKS

Amiram Eldar, Table of n, a(n) for n = 2..10000

FORMULA

a(n)=1, if n==2,3,6,7 mod 8; a(n)=3, if n==4 mod 8; a(n)=4, if n==5 mod 8; a(n)=5, if n=1 mod 8; a(n)=A007814(2n), if n==0 mod 8.

MATHEMATICA

a[n_] := IntegerExponent[((2 n - 1)!! - 1), 2]; Array[a, 100, 2] (* Amiram Eldar, Sep 13 2019 *)

CROSSREFS

Cf. A007814, A001147, A158570.

Sequence in context: A016453 A238550 A275886 * A083532 A073366 A001086

Adjacent sequences:  A158569 A158570 A158571 * A158573 A158574 A158575

KEYWORD

nonn

AUTHOR

Vladimir Shevelev, Mar 21 2009

EXTENSIONS

a(17) and a(33) corrected and more terms added by Amiram Eldar, Sep 13 2019

STATUS

approved

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Last modified June 13 05:41 EDT 2021. Contains 344981 sequences. (Running on oeis4.)