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A141355 The Jacobsthal sequence, dropping each third term. 0
1, 1, 5, 11, 43, 85, 341, 683, 2731, 5461, 21845, 43691, 174763, 349525, 1398101, 2796203, 11184811, 22369621, 89478485, 178956971, 715827883, 1431655765, 5726623061, 11453246123, 45812984491, 91625968981, 366503875925, 733007751851 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
COMMENTS
A001045 after removal of the subsequence A132805.
LINKS
FORMULA
a(2n+1)-a(2n) = 6*A015565(n).
a(4n+1)=2a(4n)-1. a(4n+2)=4a(4n+1)+1. a(4n+3)=2a(4n+2)+1. a(4n+4)=4a(4n+3)-1.
a(2n)= A082311(n). a(2n+1) = A082365(n). - R. J. Mathar, Feb 23 2009
a(n)=7*a(n-2)+8*a(n-4). G.f.: (1+x-2*x^2+4*x^3)/((1-8*x^2)*(1+x^2)). - R. J. Mathar, Feb 23 2009
CROSSREFS
Sequence in context: A260268 A129015 A209976 * A262020 A222368 A333114
KEYWORD
nonn,easy
AUTHOR
Paul Curtz, Aug 03 2008
EXTENSIONS
Edited and extended by R. J. Mathar, Feb 23 2009
STATUS
approved

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Last modified March 18 22:34 EDT 2024. Contains 370951 sequences. (Running on oeis4.)