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A155721 Positions of parity change in A033035. 0
4, 20, 84, 340, 1364, 5460, 21844, 87380, 349524, 1398100, 5592404, 22369620, 89478484, 357913940, 1431655764, 5726623060, 22906492244, 91625968980, 366503875924, 1466015503700, 5864062014804, 23456248059220, 93824992236884 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

Numbers n such that A033035(n)=(7/8)*(9^n - 1)=7*A002452(n).

FORMULA

a(n=1,2..)=(4/3)*(4^n-1)=A080674(n).

EXAMPLE

A033035(n=1..4) all are odd, then A033035(n=5..20) all are even, then A033035(n=21..84) all are odd, then A033035(n=85..340) all are even, etc.

CROSSREFS

A002452, A033035, A080674.

Sequence in context: A099898 A003489 A167682 * A084240 A080674 A110154

Adjacent sequences:  A155718 A155719 A155720 * A155722 A155723 A155724

KEYWORD

nonn

AUTHOR

Zak Seidov (zakseidov(AT)yahoo.com), Jan 25 2009

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Last modified February 17 05:54 EST 2012. Contains 205985 sequences.