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A174316
Sequence defined by a(0)=a(1)=a(2)=1, a(3)=2, a(4)=6 and the formula a(n)=2^(n-2)+2 for n>=5.
1
1, 1, 1, 2, 6, 10, 18, 34, 66, 130, 258, 514, 1026, 2050, 4098, 8194, 16386, 32770, 65538, 131074, 262146, 524290, 1048578, 2097154, 4194306, 8388610, 16777218, 33554434, 67108866, 134217730, 268435458, 536870914, 1073741826, 2147483650
OFFSET
0,4
FORMULA
G.f f: f(z)=(1+z+z^2+2*z^3+6*z^4+((2*z^5)/(1-z))+((2*z)^5/(4*(1-2*z))))
a(n) = A052548(n-2), n>3 . - R. J. Mathar, Feb 29 2016
EXAMPLE
a(5)=2^3+2=10. a(6)=2^4+2=18.
MAPLE
taylor(((1+z^3+4*z^4-4*z^5)/(1-z))+((8*z^5)/(1-2*z)), z=0, 50); v(0):=1:v(1):=1:v(2):=1:v(3):=2:v(4):=6: for n from 5 to 50 do v(n):=2^(n-2)+2:od:seq(v(n), n=0..50);
CROSSREFS
Cf. A174314.
Sequence in context: A050844 A328960 A282428 * A095357 A095358 A084481
KEYWORD
nonn,easy
AUTHOR
Richard Choulet, Mar 15 2010
STATUS
approved