OFFSET
0,5
COMMENTS
Essentially the partial sums of A052103. - R. J. Mathar, Apr 01 2008
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..1000
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/((1-x)*(1-3*x+3*x^2-3*x^3)).
A052103(n) = a(n+2) - a(n+1). (End)
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
MATHEMATICA
LinearRecurrence[{4, -6, 6, -3}, {0, 0, 0, 1}, 41] (* G. C. Greubel, Apr 15 2021 *)
PROG
(Magma) I:=[0, 0, 0, 1]; [n le 4 select I[n] else 4*Self(n-1) -6*Self(n-2) +6*Self(n-3) -3*Self(n-4): n in [1..41]]; // G. C. Greubel, Apr 15 2021
(Sage)
def A137247_list(prec):
P.<x> = PowerSeriesRing(ZZ, prec)
return P( x^3/((1-x)*(1-3*x+3*x^2-3*x^3)) ).list()
A137247_list(40) # G. C. Greubel, Apr 15 2021
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Paul Curtz, Mar 10 2008
EXTENSIONS
Name edited by Michel Marcus, Jan 29 2019
STATUS
approved