login
A129929
Binomial transform of the periodic sequence with periodic pattern 1,1,1,0,0.
3
1, 2, 4, 7, 11, 17, 29, 58, 129, 292, 639, 1333, 2666, 5188, 9999, 19388, 38166, 76332, 154261, 312703, 632171, 1271107, 2542214, 5066717, 10087066, 20099107, 40123189, 80246378, 160689174, 321892577, 644617194, 1290066428, 2580132856
OFFSET
0,2
FORMULA
a(n)=5a(n-1)-10a(n-2)+10a(n-3)-5a(n-4)+2a(n-5). - R. J. Mathar, Mar 06 2008
G.f.:-(x^2-x+1)*(x-1)^2/((2*x-1)*(x^4-2*x^3+4*x^2-3*x+1)). - Maksym Voznyy (voznyy(AT)mail.ru), Aug 12 2009
EXAMPLE
The sequence and first, 2nd, etc. difference are
1..2..4..7..11..17..29...58..129..292..639.1333..2666
..1..2..3..4...6..12..29...71......
....1..1..1..2...6...17.42......
......0..0..1..4...11..25.....
........0..1..3...7..14.....
..........1..2..4...7.........<= original series 5 rows above reappears
.......... the leading edge of the difference triangle is 5-periodic 1,1,1,0,0.
MAPLE
A129929 := proc(n) option remember ; if n <= 4 then op(n+1, [1, 2, 4, 7, 11]) ; else 5*A129929(n-1)-10*A129929(n-2)+10*A129929(n-3)-5*A129929(n-4)+2*A129929(n-5) ; fi ; end: seq(A129929(n), n=0..80) ; # R. J. Mathar, Mar 06 2008
MATHEMATICA
LinearRecurrence[{5, -10, 10, -5, 2}, {1, 2, 4, 7, 11}, 40] (* Harvey P. Dale, Oct 08 2012 *)
CROSSREFS
Sequence in context: A023427 A216116 A357926 * A360891 A073738 A137631
KEYWORD
nonn,easy,less
AUTHOR
Paul Curtz, Jun 06 2007, Jun 20 2007
EXTENSIONS
Edited by R. J. Mathar, Mar 06 2008
STATUS
approved