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 1-4 of 4 results.

A263576 Stirling transform of Fibonacci numbers (A000045).

Original entry on oeis.org

0, 1, 2, 6, 23, 101, 490, 2597, 14926, 92335, 610503, 4288517, 31848677, 249044068, 2043448968, 17540957166, 157108128963, 1464813176354, 14187155168782, 142469605397465, 1480903718595721, 15908940627242898, 176382950500197589, 2015650339677868116
Offset: 0

Views

Author

Vladimir Reshetnikov, Oct 21 2015

Keywords

Crossrefs

Programs

  • Maple
    b:= proc(n, m) option remember; `if`(n=0, (<<0|1>,
           <1|1>>^m)[1, 2], m*b(n-1, m)+b(n-1, m+1))
        end:
    a:= n-> b(n, 0):
    seq(a(n), n=0..23);  # Alois P. Heinz, Aug 03 2021
  • Mathematica
    Table[Sum[Fibonacci[k] StirlingS2[n, k], {k, 0, n}], {n, 0, 23}]
    Table[Simplify[(BellB[n, GoldenRatio] - BellB[n, 1 - GoldenRatio])/Sqrt[5]], {n, 0, 23}]

Formula

a(n) = Sum_{k=0..n} A000045(k)*Stirling2(n,k).
Sum_{k=0..n} a(k)*Stirling1(n,k) = A000045(n).
Let phi=(1+sqrt(5))/2.
a(n) = (B_n(phi)-B_n(1-phi))/sqrt(5), where B_n(x) is n-th Bell polynomial.
2*B_n(phi) = A263575(n) + a(n)*sqrt(5).
E.g.f.: (exp((exp(x)-1)*phi)-exp((exp(x)-1)*(1-phi)))/sqrt(5).
G.f.: Sum_{j>=1} Fibonacci(j)*x^j / Product_{k=1..j} (1 - k*x). - Ilya Gutkovskiy, Apr 06 2019

A323631 Stirling transform of Pell numbers (A000129).

Original entry on oeis.org

0, 1, 3, 12, 57, 305, 1798, 11531, 79707, 589426, 4634471, 38547861, 337734048, 3105588629, 29877483743, 299906019892, 3133423928557, 34002824654365, 382507638525838, 4452923233600903, 53561431659306039, 664728428775177890, 8500763141347126563, 111886109022440334593, 1513989730079050155936
Offset: 0

Views

Author

Ilya Gutkovskiy, Jan 21 2019

Keywords

Crossrefs

Programs

  • Maple
    b:= proc(n, m) option remember; `if`(n=0,
          (<<2|1>, <1|0>>^m)[1, 2], m*b(n-1, m)+b(n-1, m+1))
        end:
    a:= n-> b(n, 0):
    seq(a(n), n=0..24);  # Alois P. Heinz, Jun 23 2023
  • Mathematica
    FullSimplify[nmax = 24; CoefficientList[Series[Exp[Exp[x] - 1] Sinh[Sqrt[2] (Exp[x] - 1)]/Sqrt[2], {x, 0, nmax}], x] Range[0, nmax]!]
    Table[Sum[StirlingS2[n, k] Fibonacci[k, 2], {k, 0, n}], {n, 0, 24}]
    Table[Sum[Binomial[n, k] BellB[n - k] (BellB[k, Sqrt[2]] - BellB[k, -Sqrt[2]])/(2 Sqrt[2]), {k, 0, n}], {n, 0, 24}]

Formula

E.g.f.: exp(exp(x) - 1)*sinh(sqrt(2)*(exp(x) - 1))/sqrt(2).
a(n) = Sum_{k=0..n} Stirling2(n,k)*A000129(k).
a(n) = Sum_{k=0..n} binomial(n,k)*A000110(n-k)*A264037(k).

A323632 Stirling transform of Jacobsthal numbers (A001045).

Original entry on oeis.org

0, 1, 2, 7, 31, 152, 813, 4741, 29956, 203305, 1470795, 11276718, 91221419, 775677177, 6910797962, 64326920851, 623981351195, 6293426736344, 65867162316433, 714062197266081, 8005397253530924, 92676194887133693, 1106385117766336919, 13603803900252612966, 172082332173918135687
Offset: 0

Views

Author

Ilya Gutkovskiy, Jan 21 2019

Keywords

Crossrefs

Programs

  • Maple
    b:= proc(n, m) option remember;
         `if`(n=0, round(2^m/3), m*b(n-1, m)+b(n-1, m+1))
        end:
    a:= n-> b(n, 0):
    seq(a(n), n=0..24);  # Alois P. Heinz, Aug 06 2021
  • Mathematica
    nmax = 24; CoefficientList[Series[(Exp[2 (Exp[x] - 1)] - Exp[1 - Exp[x]])/3, {x, 0, nmax}], x] Range[0, nmax]!
    Table[Sum[StirlingS2[n, k] (2^k - (-1)^k)/3, {k, 0, n}], {n, 0, 24}]
    Table[(BellB[n, 2] - BellB[n, -1])/3, {n, 0, 24}]

Formula

E.g.f.: (exp(2*(exp(x) - 1)) - exp(1 - exp(x)))/3.
a(n) = Sum_{k=0..n} Stirling2(n,k)*A001045(k).
a(n) = (A001861(n) - A000587(n))/3.

A307361 Expansion of e.g.f. (sinh(x) + 5*cosh(x) - 5)/(3 - 2*cosh(x)).

Original entry on oeis.org

0, 1, 5, 7, 65, 151, 2105, 6847, 127265, 532231, 12365705, 63206287, 1762220465, 10645162711, 346257393305, 2413453999327, 89717615769665, 708721089607591, 29639206807284905, 261679010699505967, 12159552732032614865, 118654880542567722871, 6064946899313607640505
Offset: 0

Views

Author

Ilya Gutkovskiy, Apr 05 2019

Keywords

Crossrefs

Programs

  • Maple
    a:=series((sinh(x)+5*cosh(x)-5)/(3-2*cosh(x)),x=0,23):seq(n!*coeff(a, x, n), n=0..22); # Paolo P. Lava, Apr 12 2019
  • Mathematica
    nmax = 22; CoefficientList[Series[(Sinh[x] + 5 Cosh[x] - 5)/(3 - 2 Cosh[x]), {x, 0, nmax}], x] Range[0, nmax]!
    nmax = 22; CoefficientList[Series[Sum[j! LucasL[j] x^j/Product[(1 + k x), {k, 1, j}], {j, 1, nmax}], {x, 0, nmax}], x]
    Table[Sum[(-1)^(n - k) StirlingS2[n, k] k! LucasL[k], {k, 1, n}], {n, 0, 22}]
  • PARI
    my(x = 'x + O('x^30)); concat(0, Vec(serlaplace((sinh(x) + 5*cosh(x) - 5)/(3 - 2*cosh(x))))) \\ Michel Marcus, Apr 05 2019

Formula

G.f.: Sum_{j>=1} j!*Lucas(j)*x^j / Product_{k=1..j} (1 + k*x).
a(n) = Sum_{k=1..n} (-1)^(n-k)*Stirling2(n,k)*k!*Lucas(k).
a(n) ~ n! * (phi + (-1)^n/phi) / (2*log(phi))^(n+1), where phi = A001622 = (1+sqrt(5))/2 is the golden ratio. - Vaclav Kotesovec, Apr 05 2019
Showing 1-4 of 4 results.