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 A137247 a(n) = 4a(n-1) - 6a(n-2) + 6a(n-3) - 3a(n-4), with initial terms 0, 0, 0, 1. 0
 0, 0, 0, 1, 4, 10, 22, 49, 112, 256, 580, 1309, 2956, 6682, 15106, 34141, 77152, 174352, 394024, 890473, 2012404, 4547866, 10277806, 23227033, 52491280, 118626160, 268085740, 605852581, 1369179004, 3094236490, 6992730202, 15803018149 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,5 COMMENTS Essentially the partial sums of A052103. - R. J. Mathar, Apr 01 2008 LINKS Index entries for linear recurrences with constant coefficients, signature (4, -6, 6, -3). FORMULA From R. J. Mathar, Apr 01 2008: (Start) O.g.f.: x^3/((x-1)*(3*x^3-3*x^2+3*x-1)). A052103(n) = a(n+2) - a(n+1). (End) a(n) = -1/2 + (1/6)*(1+((1/2)*i)*108^(1/6) - (1/2)*2^(1/3))^n + (1/6)*(1-(1/2)*i)*108^(1/6) - (1/2)*2^(1/3))^n + (1/6)*(1+2^(1/3))^n, with n >= 0 and i=sqrt(-1). - Paolo P. Lava, Jun 09 2008 MAPLE a[0]:=0: a[1]:=0: a[2]:=0: a[3]:=1: for n from 4 to 30 do a[n]:=4*a[n-1]-6*a[n-2]+6*a[n-3]-3*a[n-4] end do: seq(a[n], n=0..30); # Emeric Deutsch, Mar 17 2008 CROSSREFS Cf. A052103. Sequence in context: A056112 A118430 A178452 * A155407 A318416 A124697 Adjacent sequences:  A137244 A137245 A137246 * A137248 A137249 A137250 KEYWORD nonn,easy AUTHOR Paul Curtz, Mar 10 2008 EXTENSIONS More terms from R. J. Mathar, Rolf Pleisch and Emeric Deutsch, Apr 01 2008 Name edited by Michel Marcus, Jan 29 2019 STATUS approved

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Last modified February 23 18:37 EST 2019. Contains 320438 sequences. (Running on oeis4.)