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 1-6 of 6 results.

A343787 Number of ordered partitions of an n-set without blocks of size 4.

Original entry on oeis.org

1, 1, 3, 13, 74, 531, 4563, 45753, 524345, 6760039, 96837333, 1525909903, 26230304235, 488472319271, 9796281435125, 210496933103743, 4824574494068495, 117490079786298641, 3029472152485535343, 82454398253005541089, 2362311059301928969755, 71063998308414194250901
Offset: 0

Views

Author

Ilya Gutkovskiy, Apr 29 2021

Keywords

Crossrefs

Programs

  • Maple
    a:= proc(n) option remember; `if`(n=0, 1, add(
          `if`(j=4, 0, a(n-j)*binomial(n, j)), j=1..n))
        end:
    seq(a(n), n=0..21);  # Alois P. Heinz, Apr 29 2021
  • Mathematica
    nmax = 21; CoefficientList[Series[1/(2 + x^4/4! - Exp[x]), {x, 0, nmax}], x] Range[0, nmax]!
    a[n_] := a[n] = If[n == 0, 1, Sum[If[k == 4, 0, Binomial[n, k] a[n - k]], {k, 1, n}]]; Table[a[n], {n, 0, 21}]

Formula

E.g.f.: 1 / (2 + x^4/4! - exp(x)).

A343788 Number of ordered partitions of an n-set without blocks of size 5.

Original entry on oeis.org

1, 1, 3, 13, 75, 540, 4671, 47125, 543371, 7048453, 101589591, 1610634433, 27856938387, 521953586233, 10532102378983, 227699187663961, 5250934660206219, 128659152359921997, 3337861722359261475, 91406502629924948053, 2634888477782107003707, 79751100251346500871481
Offset: 0

Views

Author

Ilya Gutkovskiy, Apr 29 2021

Keywords

Crossrefs

Programs

  • Maple
    a:= proc(n) option remember; `if`(n=0, 1, add(
          `if`(j=5, 0, a(n-j)*binomial(n, j)), j=1..n))
        end:
    seq(a(n), n=0..21);  # Alois P. Heinz, Apr 29 2021
  • Mathematica
    nmax = 21; CoefficientList[Series[1/(2 + x^5/5! - Exp[x]), {x, 0, nmax}], x] Range[0, nmax]!
    a[n_] := a[n] = If[n == 0, 1, Sum[If[k == 5, 0, Binomial[n, k] a[n - k]], {k, 1, n}]]; Table[a[n], {n, 0, 21}]

Formula

E.g.f.: 1 / (2 + x^5/5! - exp(x)).

A343789 Number of ordered partitions of an n-set without blocks of size 6.

Original entry on oeis.org

1, 1, 3, 13, 75, 541, 4682, 47279, 545611, 7083565, 102182883, 1621425829, 28067555607, 526349480593, 10629883138059, 230009622202373, 5308749619032571, 130186940173803053, 3380385112758108315, 92650130825921846941, 2673020491585091254035, 80974418589343644492805
Offset: 0

Views

Author

Ilya Gutkovskiy, Apr 29 2021

Keywords

Crossrefs

Programs

  • Maple
    a:= proc(n) option remember; `if`(n=0, 1, add(
          `if`(j=6, 0, a(n-j)*binomial(n, j)), j=1..n))
        end:
    seq(a(n), n=0..21);  # Alois P. Heinz, Apr 29 2021
  • Mathematica
    nmax = 21; CoefficientList[Series[1/(2 + x^6/6! - Exp[x]), {x, 0, nmax}], x] Range[0, nmax]!
    a[n_] := a[n] = If[n == 0, 1, Sum[If[k == 6, 0, Binomial[n, k] a[n - k]], {k, 1, n}]]; Table[a[n], {n, 0, 21}]

Formula

E.g.f.: 1 / (2 + x^6/6! - exp(x)).

A343790 Number of ordered partitions of an n-set without blocks of size 7.

Original entry on oeis.org

1, 1, 3, 13, 75, 541, 4683, 47292, 545819, 7086973, 102242283, 1622530933, 28089498891, 526813752973, 10640325166227, 230258631645913, 5315029292965675, 130353994525735677, 3385061859378821547, 92787606222541942477, 2677254928352340708075, 81110818086045534369661
Offset: 0

Views

Author

Ilya Gutkovskiy, Apr 29 2021

Keywords

Crossrefs

Programs

  • Maple
    a:= proc(n) option remember; `if`(n=0, 1, add(
          `if`(j=7, 0, a(n-j)*binomial(n, j)), j=1..n))
        end:
    seq(a(n), n=0..21);  # Alois P. Heinz, Apr 29 2021
  • Mathematica
    nmax = 21; CoefficientList[Series[1/(2 + x^7/7! - Exp[x]), {x, 0, nmax}], x] Range[0, nmax]!
    a[n_] := a[n] = If[n == 0, 1, Sum[If[k == 7, 0, Binomial[n, k] a[n - k]], {k, 1, n}]]; Table[a[n], {n, 0, 21}]

Formula

E.g.f.: 1 / (2 + x^7/7! - exp(x)).

A343791 Number of ordered partitions of an n-set without blocks of size 8.

Original entry on oeis.org

1, 1, 3, 13, 75, 541, 4683, 47293, 545834, 7087243, 102247203, 1622625313, 28091415135, 526854986737, 10641264928479, 230281282588513, 5315605563021465, 130369438065006551, 3385496924633886429, 92800464391224494215, 2677652842774247060805, 81123688691904430522831
Offset: 0

Views

Author

Ilya Gutkovskiy, Apr 29 2021

Keywords

Crossrefs

Programs

  • Maple
    a:= proc(n) option remember; `if`(n=0, 1, add(
          `if`(j=8, 0, a(n-j)*binomial(n, j)), j=1..n))
        end:
    seq(a(n), n=0..21);  # Alois P. Heinz, Apr 29 2021
  • Mathematica
    nmax = 21; CoefficientList[Series[1/(2 + x^8/8! - Exp[x]), {x, 0, nmax}], x] Range[0, nmax]!
    a[n_] := a[n] = If[n == 0, 1, Sum[If[k == 8, 0, Binomial[n, k] a[n - k]], {k, 1, n}]]; Table[a[n], {n, 0, 21}]

Formula

E.g.f.: 1 / (2 + x^8/8! - exp(x)).

A343792 Number of ordered partitions of an n-set without blocks of size 9.

Original entry on oeis.org

1, 1, 3, 13, 75, 541, 4683, 47293, 545835, 7087260, 102247543, 1622632133, 28091557915, 526858128161, 10641337741219, 230283060907913, 5315651289289195, 130370674248854021, 3385532005327322503, 92801507648842580769, 2677685300845992661475, 81124743440296074264381
Offset: 0

Views

Author

Ilya Gutkovskiy, Apr 29 2021

Keywords

Crossrefs

Programs

  • Maple
    a:= proc(n) option remember; `if`(n=0, 1, add(
          `if`(j=9, 0, a(n-j)*binomial(n, j)), j=1..n))
        end:
    seq(a(n), n=0..21);  # Alois P. Heinz, Apr 29 2021
  • Mathematica
    nmax = 21; CoefficientList[Series[1/(2 + x^9/9! - Exp[x]), {x, 0, nmax}], x] Range[0, nmax]!
    a[n_] := a[n] = If[n == 0, 1, Sum[If[k == 9, 0, Binomial[n, k] a[n - k]], {k, 1, n}]]; Table[a[n], {n, 0, 21}]

Formula

E.g.f.: 1 / (2 + x^9/9! - exp(x)).
Showing 1-6 of 6 results.