A158572 - OEIS

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A158572

a(n) = A007814((2n-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