login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A291389 p-INVERT of (1,1,0,0,0,0,...), where p(S) = (1 - 5 S)^2. 3

%I #7 Sep 09 2017 21:43:16

%S 10,85,650,4700,32750,222375,1481250,9721875,63062500,405175000,

%T 2582687500,16353078125,102955156250,644991640625,4023367968750,

%U 25002220312500,154848222656250,956155732421875,5888138769531250,36171585068359375,221714776953125000

%N p-INVERT of (1,1,0,0,0,0,...), where p(S) = (1 - 5 S)^2.

%C Suppose s = (c(0), c(1), c(2), ...) is a sequence and p(S) is a polynomial. Let S(x) = c(0)*x + c(1)*x^2 + c(2)*x^3 + ... and T(x) = (-p(0) + 1/p(S(x)))/x. The p-INVERT of s is the sequence t(s) of coefficients in the Maclaurin series for T(x). Taking p(S) = 1 - S gives the "INVERT" transform of s, so that p-INVERT is a generalization of the "INVERT" transform (e.g., A033453).

%C See A291382 for a guide to related sequences.

%C All terms = 0 mod 5. - _Muniru A Asiru_, Sep 07 2017

%H Clark Kimberling, <a href="/A291389/b291389.txt">Table of n, a(n) for n = 0..1000</a>

%H <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (10, -15, -50, -25)

%F G.f.: -((5 (1 + x) (-2 + 5 x + 5 x^2))/(-1 + 5 x + 5 x^2)^2).

%F a(n) = 10*a(n-1) - 15*a(n-2) - 50*a(n-3) - 25*a(n-4) for n >= 5.

%t z = 60; s = x + x^2; p = (1 - 5 s)^2;

%t Drop[CoefficientList[Series[s, {x, 0, z}], x], 1] (* A019590 *)

%t u = Drop[CoefficientList[Series[1/p, {x, 0, z}], x], 1] (* A291389 *)

%t u / 5 (* A291390 *)

%o (GAP)

%o a:=5*[2,17,130,940];; for n in [5..10^2] do a[n]:=10*a[n-1]-15*a[n-2]-50*a[n-3]-25*a[n-4]; od; a; # _Muniru A Asiru_, Sep 07 2017

%Y Cf. A019590, A291382, A291390.

%K nonn,easy

%O 0,1

%A _Clark Kimberling_, Sep 04 2017

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 28 22:04 EDT 2024. Contains 371254 sequences. (Running on oeis4.)