login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A200672 Partial sums of A173862. 4
1, 2, 3, 5, 7, 9, 13, 17, 21, 29, 37, 45, 61, 77, 93, 125, 157, 189, 253, 317, 381, 509, 637, 765, 1021, 1277, 1533, 2045, 2557, 3069, 4093, 5117, 6141, 8189, 10237, 12285, 16381, 20477, 24573, 32765, 40957, 49149, 65533, 81917, 98301, 131069, 163837, 196605 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Partial sums of powers of 2 repeated 3 times.

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Shatalov A. A, The Cupola Algorithm Data And The Modulation-37 The Natural Sciences Aspect And The Using For Analysis Of Ancient Layouts, European Journal Of Natural History, 2007 No. 1, p. 35.

Index entries for linear recurrences with constant coefficients, signature (1,0,2,-2).

FORMULA

G.f.: x*(1+x+x^2) / ( (x-1)*(2*x^3-1) ). - R. J. Mathar, Nov 28 2011

a(3*n) = 3*(2^n-1) = 3*A000225(n). - Philippe Deléham, Mar 13 2013

a(n) = 2*a(n-3) + 3 for n > 3. - Yuchun Ji, Nov 16 2018

EXAMPLE

a(4) = 1+1+1+2 = 5.

MATHEMATICA

CoefficientList[Series[(1 + x + x^2) / ((x - 1) (2 x^3 - 1)), {x, 0, 50}], x] (* Vincenzo Librandi, Nov 16 2018 *)

PROG

(BASIC) for i=0 to 12 : for j=1 to 3 : s=s+2^i : print s : next j : next i

(MAGMA) I:=[1, 2, 3, 5]; [n le 4 select I[n] else Self(n-1) + 2*Self(n-3)- 2*Self(n-4): n in [1..50]]; // Vincenzo Librandi, Nov 16 2018

CROSSREFS

Cf. A027383, A173862.

Sequence in context: A028870 A057886 A302835 * A332686 A069999 A271661

Adjacent sequences:  A200669 A200670 A200671 * A200673 A200674 A200675

KEYWORD

nonn

AUTHOR

Jeremy Gardiner, Nov 20 2011

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 10 00:05 EDT 2020. Contains 333392 sequences. (Running on oeis4.)