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 A109165 a(n) = 5*a(n-2) - 2*a(n-4), n >= 4; a(n) = (1/6)*(-1)^n + 4/3)*2^n - 1/2. 0
 1, 2, 5, 10, 23, 46, 105, 210, 479, 958, 2185, 4370, 9967, 19934, 45465, 90930, 207391, 414782, 946025, 1892050, 4315343, 8630686, 19684665, 39369330, 89792639, 179585278, 409593865, 819187730, 1868384047, 3736768094, 8522732505 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,2 LINKS FORMULA a(2n) = A107839(n), a(2n+1) = A106709(n+1), a(n) - a(n-1) = A005824(n+2);; G.f. (2*x+1)/(1-5*x^2+2*x^4) PROG Floretion Algebra Multiplication Program, FAMP Code: 4kbaseksigcycsumseq[ - .25'i - .25i' + .25'ii' + .25'jj' + .25'kk' + .25'jk' + .25'kj' + .25e], sumtype: (Y[15], *, vesy) CROSSREFS Cf. A107839, A106709, A005824, A054486. Sequence in context: A007182 A191386 A026677 * A018344 A284181 A291249 Adjacent sequences:  A109162 A109163 A109164 * A109166 A109167 A109168 KEYWORD easy,nonn AUTHOR Creighton Dement, Aug 18 2005 STATUS approved

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