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A155485 a(n) = 5^n + (1 - 4^n)/3. 1
1, 4, 20, 104, 540, 2784, 14260, 72664, 368780, 1865744, 9416100, 47430024, 238548220, 1198333504, 6014037140, 30159664184, 151156234860, 757212830064, 3791790773380, 18981860359144, 95000927764700, 475371142699424, 2378321729000820, 11897472707018904 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
LINKS
FORMULA
a(n) = A000351(n) - A001045(2n).
a(n) = 10a(n-1) - 29a(n-2) + 20a(n-3), as in A097165.
From R. J. Mathar, Feb 27 2009: (Start)
G.f.: (1-3x)^2/((1-x)(1-4x)(1-5x)).
a(n) = A097165(n) - 3*A097165(n-1). (End)
PROG
(Magma) [5^n+(1-4^n)/3: n in [0..30]]; // Vincenzo Librandi, Aug 07 2011
CROSSREFS
Sequence in context: A168606 A229135 A226198 * A155181 A082761 A076035
KEYWORD
nonn,easy
AUTHOR
Paul Curtz, Jan 23 2009
EXTENSIONS
Edited, Lava definition adopted, and extended by R. J. Mathar, Feb 27 2009
STATUS
approved

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Last modified April 16 03:22 EDT 2024. Contains 371696 sequences. (Running on oeis4.)