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.

Showing 1-2 of 2 results.

A055856 Susceptibility series H_4 for 2-dimensional Ising model (divided by 2).

Original entry on oeis.org

1, 16, 90, 328, 888, 2016, 3994, 7212, 12070, 19112, 28846, 41976, 59116, 81132, 108738, 142972, 184638, 234952, 294806, 365596, 448296, 544492, 655230, 782292, 926794, 1090716, 1275238, 1482548, 1713880, 1971636, 2257102, 2572896, 2920350, 3302308, 3720138
Offset: 0

Views

Author

Wolfdieter Lang, Jun 07 2000

Keywords

Crossrefs

Programs

  • Magma
    R:=PowerSeriesRing(Integers(), 40); Coefficients(R!( (1 +15*x +71*x^2 +192*x^3 +326*x^4 +388*x^5 +326*x^6 +192*x^7 + 71*x^8 +15*x^9 +x^10)/((1-x^3)*(1-x^2)^3*(1-x)) )); // G. C. Greubel, Jan 16 2020
    
  • Maple
    1,seq( simplify( (4794*n^4 +19194*n^2 +3349 -81*(-1)^n*(2*n^2 +5) + 512*ChebyshevT(n, -1/2))/1728 ), n=1..40); # G. C. Greubel, Jan 16 2020
  • Mathematica
    Join[{1}, Table[(4794*n^4 +19194*n^2 +3349 -81*(-1)^n*(2*n^2 +5) + 512*ChebyshevT[n, -1/2])/1728, {n,40}]] (* G. C. Greubel, Jan 16 2020 *)
    LinearRecurrence[{1,3,-2,-4,0,4,2,-3,-1,1},{1,16,90,328,888,2016,3994,7212,12070,19112,28846},40] (* Harvey P. Dale, Jul 24 2021 *)
  • PARI
    Vec((1 +15*x +71*x^2 +192*x^3 +326*x^4 +388*x^5 +326*x^6 +192*x^7 + 71*x^8 +15*x^9 +x^10)/((1-x^3)*(1-x)^4*(1+x)^3) + O(x^40)) \\ Colin Barker, Dec 10 2016
    
  • Sage
    [1]+[(4794*n^4 +19194*n^2 +3349 -81*(-1)^n*(2*n^2 +5) + 512*chebyshev_T(n, -1/2))/1728 for n in (1..40)] # G. C. Greubel, Jan 16 2020

Formula

G.f.: (1 + 15*x + 71*x^2 + 192*x^3 + 326*x^4 + 388*x^5 + 326*x^6 + 192*x^7 + 71*x^8 + 15*x^9 + x^10)/((1-x^3)*(1-x)^4*(1+x)^3).
a(n) = (4794*n^4 + 19194*n^2 + 3349 - 81*(-1)^n*(2*n^2 + 5) + 512*ChebyshevT(n, -1/2))/1728, for n >= 1, with a(0) = 1. - G. C. Greubel, Jan 16 2020

A055855 Convolution of A055854 with A011782.

Original entry on oeis.org

0, 1, 10, 64, 328, 1462, 5908, 22180, 78592, 265729, 864146, 2719028, 8316200, 24814832, 72453344, 207502016, 584094080, 1618757120, 4423347200, 11932579840, 31812874240, 83901227008, 219074805760, 566754967552
Offset: 0

Views

Author

Wolfdieter Lang May 30 2000

Keywords

Comments

Tenth column of triangle A055587.
T(n,8) of array T as in A049600.

Crossrefs

Programs

  • Magma
    R:=PowerSeriesRing(Integers(), 30); [0] cat Coefficients(R!( x*(1-x)^8/(1-2*x)^9 )); // G. C. Greubel, Jan 16 2020
    
  • Maple
    seq(coeff(series(x*(1-x)^8/(1-2*x)^9, x, n+1), x, n), n = 0..30); # G. C. Greubel, Jan 16 2020
  • Mathematica
    CoefficientList[Series[x*(1-x)^8/(1-2*x)^9, {x,0,30}], x] (* G. C. Greubel, Jan 16 2020 *)
  • PARI
    my(x='x+O('x^30)); concat([0], Vec(x*(1-x)^8/(1-2*x)^9)) \\ G. C. Greubel, Jan 16 2020
    
  • Sage
    def A055855_list(prec):
        P. = PowerSeriesRing(ZZ, prec)
        return P( x*(1-x)^8/(1-2*x)^9 ).list()
    A055855_list(30) # G. C. Greubel, Jan 16 2020

Formula

a(n) = T(n, 8) = A055587(n+8, 9).
G.f.: x*(1-x)^8/(1-2*x)^9.
Showing 1-2 of 2 results.