A081674 - OEIS

%I #28 Aug 29 2024 21:09:52

%S 0,1,6,29,130,561,2366,9829,40410,164921,669526,2707629,10919090,

%T 43942081,176565486,708653429,2841788170,11388676041,45619274246,

%U 182670807229,731264359650,2926800830801,11712433499806,46865424529029,187508769705530,750176293590361,3001128818666166

%N Generalized Poly-Bernoulli numbers.

%C Binomial transform of A027649. Inverse binomial transform of A081675.

%C With offset 1, partial sums of A085350. - _Paul Barry_, Jun 24 2003

%C Number of walks of length 2n+2 between two nodes at distance 4 in the cycle graph C_12. - _Herbert Kociemba_, Jul 05 2004

%H Vincenzo Librandi, <a href="/A081674/b081674.txt">Table of n, a(n) for n = 0..1000</a>

%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (8,-19,12).

%F a(n) = ((4^(n+1) - 1)/3 - 3^n)/2 = (4*4^n - 3*3^n - 1)/6.

%F a(n) = (A002450(n+1) + A000244(n))/2.

%F G.f.: x*(1-2*x)/((1-x)*(1-3*x)*(1-4*x)).

%F From _Elmo R. Oliveira_, Aug 29 2024: (Start)

%F E.g.f.: exp(x)*(4*exp(3*x) - 3*exp(2*x) - 1)/6.

%F a(n) = 8*a(n-1) - 19*a(n-2) + 12*a(n-3) for n > 2. (End)

%t Join[{a=0,b=1},Table[c=7*b-12*a-1;a=b;b=c,{n,60}]] (* _Vladimir Joseph Stephan Orlovsky_, Jan 19 2011 *)

%t CoefficientList[Series[(x(1-2x))/((1-x)(1-3x)(1-4x)),{x,0,30}],x] (* or *) LinearRecurrence[{8,-19,12},{0,1,6},30] (* _Harvey P. Dale_, Nov 28 2018 *)

%o (Magma) [((4^(n+1)-1)/3-3^n)/2: n in [0..30]]; // _Vincenzo Librandi_, Jul 17 2011

%Y Cf. A000244, A002450, A027649, A081675, A085350.

%K easy,nonn

%O 0,3

%A _Paul Barry_, Mar 28 2003