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.

A364430 G.f. satisfies A(x) = 1 - x*A(x)*(1 - 2*A(x)^3).

Original entry on oeis.org

1, 1, 7, 61, 603, 6443, 72517, 846995, 10170685, 124780525, 1557347467, 19710577873, 252386341335, 3263626001751, 42558647522697, 559032393114023, 7390085367865081, 98242108076244665, 1312529311579827631, 17613845480108029957, 237322279651518516019
Offset: 0

Views

Author

Seiichi Manyama, Jul 24 2023

Keywords

Crossrefs

Programs

  • Maple
    A364430 := proc(n)
        (-1)^n*add((-2)^k* binomial(n,k) * binomial(n+3*k+1,n) / (n+3*k+1),k=0..n) ;
    end proc:
    seq(A364430(n),n=0..70); # R. J. Mathar, Jul 25 2023
  • PARI
    a(n) = (-1)^n*sum(k=0, n, (-2)^k*binomial(n, k)*binomial(n+3*k+1, n)/(n+3*k+1));

Formula

a(n) = (-1)^n * Sum_{k=0..n} (-2)^k * binomial(n,k) * binomial(n+3*k+1,n) / (n+3*k+1).
D-finite with recurrence 3*n*(3*n-1)*(3*n+1)*a(n) +(-566*n^3 +1335*n^2 -1105*n +312)*a(n-1) +3*(943*n^3 -5739*n^2 +11016*n -6748)*a(n-2) +18*(-250*n^3 +2499*n^2 -8233*n +8938)*a(n-3) +27*(n-4)*(31*n^2 -314*n +735)*a(n-4) +81*(10*n -51)*(n-4) *(n-5)*a(n-5) +243*(n-5) *(n-6)*(n-4)*a(n-6)=0. - R. J. Mathar, Jul 25 2023

A364432 G.f. satisfies A(x) = 1 + x*A(x)*(2 + A(x)^3).

Original entry on oeis.org

1, 3, 18, 162, 1728, 20169, 249318, 3207600, 42500700, 576012060, 7947785448, 111269613006, 1576658688480, 22568473199358, 325855352769588, 4740157737123696, 69405108247439676, 1022070746845708740, 15127922880893671704, 224931239520535651464
Offset: 0

Views

Author

Seiichi Manyama, Jul 24 2023

Keywords

Crossrefs

Programs

  • Maple
    A364432 := proc(n)
        add(2^(n-k)* binomial(n,k) * binomial(n+3*k+1,n) / (n+3*k+1),k=0..n) ;
    end proc:
    seq(A364432(n),n=0..70); # R. J. Mathar, Jul 25 2023
  • PARI
    a(n) = sum(k=0, n, 2^(n-k)*binomial(n, k)*binomial(n+3*k+1, n)/(n+3*k+1));

Formula

a(n) = Sum_{k=0..n} 2^(n-k) * binomial(n,k) * binomial(n+3*k+1,n) / (n+3*k+1).
D-finite with recurrence 3*n*(3*n-1)*(3*n+1)*a(n) +2*(-74*n^3 -375*n^2+ 665*n -252)*a(n-1) +12*(-337*n^3 +1941*n^2 -2984*n +1092)*a(n-2) +144*(-70*n^3 +861*n^2 -3347*n +4152)*a(n-3) +432*(n-4)*(31*n^2 -314*n +735)*a(n-4) -2592*(10*n-51) *(n-4)*(n-5)*a(n-5) +15552*(n-5)*(n-6) *(n-4)*a(n-6)=0. - R. J. Mathar, Jul 25 2023
Showing 1-2 of 2 results.