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 A072329 a(n+1)=3*a(n-2)+2*a(n-1) a(n)=x^n+y^n+z^n. 0
 3, 0, 4, 9, 8, 30, 43, 84, 176, 297, 604, 1122, 2099, 4056, 7564, 14409, 27296, 51510, 97819, 184908, 350168, 663273, 1255060, 2377050 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,1 COMMENTS With the terms indexed as shown, has property that n prime or n=2^k or n=3^k => n divides a(n). LINKS FORMULA a(n)=x^n+y^n+z^n e=-1/2+i*sqrt(3)/2, e^2=-1/2-i*sqrt(3)/2 x=((3+sqrt(9-32/27)/2)^(1/3)+((3-sqrt(9-32/27))/2)^(1/3) y=e*((3+sqrt(9-32/27))/2)^(1/3)+(e^2)*((3-sqrt(9-32/27))/2)^(1/3) z=(e^2)*((3+sqrt(9-32/27)/2)^(1/3)+e*((3-sqrt(9-32/27))/2)^(1/3) G.f.: g(x)=(3-2*x^2)/(1-2*x^2-3*x^3) CROSSREFS Cf. A001608. Sequence in context: A088230 A181482 A330420 * A068630 A309764 A079406 Adjacent sequences:  A072326 A072327 A072328 * A072330 A072331 A072332 KEYWORD easy,nonn AUTHOR Miklos Kristof, Jul 15 2002 EXTENSIONS Corrected by T. D. Noe, Nov 07 2006 STATUS approved

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Last modified April 1 02:15 EDT 2020. Contains 333153 sequences. (Running on oeis4.)