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A080643
a(0)=0; for n>0, a(n) = 4^n - 2*3^(n-1).
3
0, 2, 10, 46, 202, 862, 3610, 14926, 61162, 249022, 1009210, 4076206, 16422922, 66045982, 265246810, 1064175886, 4266269482, 17093775742, 68461196410, 274103065966, 1097187104842, 4391072942302, 17571265338010, 70305982058446, 281286690353002, 1125335047769662
OFFSET
0,2
FORMULA
G.f.: 2*x*(1-2*x)/((1-3*x)*(1-4*x)). - Colin Barker, Jan 20 2012
MATHEMATICA
Join[{0}, Table[4^n-2*3^(n-1), {n, 30}]] (* or *) LinearRecurrence[{7, -12}, {0, 2, 10}, 30] (* Harvey P. Dale, Dec 29 2023 *)
CROSSREFS
Complement of A025192 in 4^n.
Sequence in context: A191813 A360412 A181294 * A032389 A290923 A106709
KEYWORD
nonn,easy
AUTHOR
Max Alekseyev, Feb 26 2003
STATUS
approved