cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A298564 a(n) = (3^(n+2)+11)/2 - 5*2^(n+1) + 2*n.

Original entry on oeis.org

0, 1, 10, 53, 218, 789, 2658, 8581, 26986, 83477, 255506, 776709, 2350554, 7092565, 21359554, 64242437, 193054922, 579820053, 1740770802, 5224933765, 15680044090, 47050617941, 141172825250, 423560418693, 1270765142058, 3812463198229, 11437725138898, 34313846505221, 102942881692826
Offset: 0

Views

Author

M. F. Hasler, Jan 21 2018

Keywords

Comments

Partial sums of A281773; first differences of A285361.

Crossrefs

Programs

  • Mathematica
    Array[(3^(# + 2) + 11)/2 - 5*2^(# + 1) + 2 # &, 29, 0] (* or *)
    CoefficientList[Series[x (1 + 3 x)/((3 x - 1) (2 x - 1) (x - 1)^2), {x, 0, 28}], x] (* Michael De Vlieger, Jan 21 2018 *)
  • PARI
    A298564(n)=2*n-5<<(n+1)+3^(n+2)\2+5
    
  • Python
    def A298564list(n):
        def generator():
            a, b, c = 5, 3, 0
            while True:
                yield c
                a *= 2
                b *= 3
                c += 2 - a + b
        a = generator()
        return [next(a) for _ in range(n)]
    print(A298564list(29)) # Peter Luschny, Jan 22 2018

Formula

G.f.: x*(1+3*x) / ( (3*x-1)*(2*x-1)*(x-1)^2 ). - R. J. Mathar, Jan 21 2018
a(n) = A249999(n-1) +3*A249999(n-2). - R. J. Mathar, Jan 21 2018