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A140360
Inverse binomial transform of A140359.
4
1, 0, 5, -5, 15, -25, 55, -105, 215, -425, 855, -1705, 3415, -6825, 13655, -27305, 54615, -109225, 218455, -436905, 873815, -1747625, 3495255, -6990505, 13981015, -27962025, 55924055, -111848105, 223696215, -447392425, 894784855, -1789569705, 3579139415
OFFSET
0,3
COMMENTS
For p*Jacobsthal numbers A001045, p=2: A078008 (A001045 differences, they are companions) or 1, 2*A001045(n), also in A133494; p=3: A062510; p=4: see A097073; p=6: A092297.
FORMULA
G.f.: (-3*x^2-x-1) / (2*x^2-x-1).
a(n) = (-5*(-1 + (-2)^(n-1)))/3, for n>0. - Andres Cicuttin, Apr 15 2016
a(n) = 5 - 2*a(n-1), for n>2. - Andres Cicuttin, Apr 15 2016
MAPLE
a:= n-> `if`(n=0, 1, (<<0|1>, <2|-1>>^(n-1). <<0, 5>>)[1, 1]):
seq(a(n), n=0..30); # Alois P. Heinz, Dec 28 2010
MATHEMATICA
{1}~Join~Table[(-5 (-1 + (-2)^(n - 1)))/3, {n, 32}] (* or *)
CoefficientList[Series[(-3 x^2 - x - 1)/(2 x^2 - x - 1), {x, 0, 32}], x] (* Michael De Vlieger, Apr 15 2016 *)
CROSSREFS
Sequence in context: A185905 A341244 A050341 * A302511 A178821 A145599
KEYWORD
sign
AUTHOR
Paul Curtz, Jun 24 2008
EXTENSIONS
More terms from Alois P. Heinz, Dec 28 2010
STATUS
approved