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

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A158561 a(n) = ((2^n)*((2^n)+1) - (2^(n-1))*((2^(n-1))+1))/2, a(1)=3. 1
 3, 7, 26, 100, 392, 1552, 6176, 24640, 98432, 393472, 1573376, 6292480, 25167872, 100667392, 402661376, 1610629120, 6442483712, 25769869312, 103079346176, 412317122560, 1649267965952, 6597070815232, 26388281163776, 105553120460800, 422212473454592 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS a(n) gives the number of elements with the length of n-digits, base B, in the addition matrix <0;B^n -1> x <0;B^n -1>. a(1)=B*(B+1)/2. a(n)=((B^n)*((B^n)+1) - (B^(n-1))*((B^(n-1))+1))/2. Essentially the same as A049775. [R. J. Mathar, Mar 26 2009] LINKS Harvey P. Dale, Table of n, a(n) for n = 1..1000 Index entries for linear recurrences with constant coefficients, signature (6,-8) FORMULA G.f.: x*(1-x)*(3-8*x)/((1-2*x)*(1-4*x)). [Jaume Oliver Lafont, Mar 27 2009] G.f.: (3-11*x+8*x^2)/(1-6*x+8*x^2). - Harvey P. Dale, Feb 25 2017 MATHEMATICA LinearRecurrence[{6, -8}, {3, 7, 26}, 30] (* Harvey P. Dale, Feb 25 2017 *) CROSSREFS Cf. A000217 Cf. A006516. [Jaume Oliver Lafont, Mar 27 2009] Sequence in context: A215018 A069738 A057005 * A252786 A108217 A120120 Adjacent sequences: A158558 A158559 A158560 * A158562 A158563 A158564 KEYWORD easy,nonn AUTHOR Ctibor O. Zizka, Mar 21 2009 EXTENSIONS More terms from Harvey P. Dale, Feb 25 2017 STATUS approved

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.

Last modified July 12 19:59 EDT 2024. Contains 374252 sequences. (Running on oeis4.)