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.

A055843 Expansion of (1+3*x)/(1-x)^10.

Original entry on oeis.org

1, 13, 85, 385, 1375, 4147, 11011, 26455, 58630, 121550, 238238, 445094, 797810, 1379210, 2309450, 3759074, 5965487, 9253475, 14060475, 20967375, 30735705, 44352165, 63081525, 88529025, 122713500, 168152556, 227961228, 305965660, 406833460, 536222500, 700950052
Offset: 0

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Author

Barry E. Williams, May 30 2000

Keywords

Comments

Partial sums of A052181.

References

  • Albert H. Beiler, Recreations in the Theory of Numbers, Dover, N.Y., 1964, pp. 194-196.

Crossrefs

Cf. A052181.
Cf. A093561 ((4, 1) Pascal, column m=9).

Programs

  • GAP
    List([0..30], n-> (4*n+9)*Binomial(n+8, 8)/9 ); # G. C. Greubel, Jan 21 2020
  • Magma
    [(4*n+9)*Binomial(n+8, 8)/9: n in [0..30]]; // G. C. Greubel, Jan 21 2020
    
  • Maple
    seq( (4*n+9)*binomial(n+8, 8)/9, n=0..30); # G. C. Greubel, Jan 21 2020
  • Mathematica
    Table[4*Binomial[n+9,9] - 3*Binomial[n+8,8], {n,0,30}] (* G. C. Greubel, Jan 21 2020 *)
  • PARI
    vector(31, n, (4*n+5)*binomial(n+7, 8)/9) \\ G. C. Greubel, Jan 21 2020
    
  • Sage
    [(4*n+9)*binomial(n+8, 8)/9 for n in (0..30)] # G. C. Greubel, Jan 21 2020
    

Formula

a(n) = (4*n+9)*binomial(n+8, 8)/9.
G.f.: (1+3*x)/(1-x)^10.
a(n) = 4*binomial(n+9,9) - 3*binomial(n+8,8). - G. C. Greubel, Jan 21 2020
Sum_{n>=0} 1/a(n) = 9437184*Pi/24035 + 56623104*log(2)/24035 - 482087736/168245. - Amiram Eldar, Feb 17 2023