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.

Previous Showing 11-15 of 15 results.

A230129 Number of permutations of order n with the length of longest run equal 6.

Original entry on oeis.org

2, 24, 274, 3204, 39420, 514296, 7137818, 105318770, 1649355338, 27356466626, 479446719522, 8858271760146, 172151975433756, 3511580514677006, 75032190827549478, 1676210011258705592, 39082263260517298658, 949481770375318700914, 23998362106238648271276
Offset: 6

Views

Author

Alois P. Heinz, Oct 10 2013

Keywords

Crossrefs

Column l=6 of A211318.
A diagonal of A010026.

Programs

  • Maple
    g:= proc(u, o, t) option remember; `if`(u+o=0, 1,
           add(g(o+j-1, u-j, 2), j=1..u) +`if`(t<6,
           add(g(u+j-1, o-j, t+1), j=1..o), 0))
        end:
    b:= proc(u, o, t) option remember; `if`(t=6, g(u, o, t),
           add(b(o+j-1, u-j, 2), j=1..u)+
           add(b(u+j-1, o-j, t+1), j=1..o))
        end:
    a:= n-> add(b(j-1, n-j, 1), j=1..n):
    seq(a(n), n=6..30);
  • Mathematica
    length = 6;
    g[u_, o_, t_] := g[u, o, t] = If[u+o == 0, 1, Sum[g[o + j - 1, u - j, 2], {j, 1, u}] + If[tJean-François Alcover, Aug 18 2018, after Alois P. Heinz *)

A230130 Number of permutations of order n with the length of the longest run equal to 7.

Original entry on oeis.org

2, 28, 362, 4720, 64020, 913440, 13760472, 219040274, 3681354658, 65231186514, 1216489698082, 23832126613268, 489566931234322, 10526180908026522, 236475437787567496, 5541690642862917134, 135258139216049657102, 3433304061341792767884, 90508485528963754208076
Offset: 7

Views

Author

Alois P. Heinz, Oct 10 2013

Keywords

Crossrefs

Column l=7 of A211318.
A diagonal of A010026.

Programs

  • Maple
    g:= proc(u, o, t) option remember; `if`(u+o=0, 1,
           add(g(o+j-1, u-j, 2), j=1..u) +`if`(t<7,
           add(g(u+j-1, o-j, t+1), j=1..o), 0))
        end:
    b:= proc(u, o, t) option remember; `if`(t=7, g(u, o, t),
           add(b(o+j-1, u-j, 2), j=1..u)+
           add(b(u+j-1, o-j, t+1), j=1..o))
        end:
    a:= n-> add(b(j-1, n-j, 1), j=1..n):
    seq(a(n), n=7..30);
  • Mathematica
    length = 7;
    g[u_, o_, t_] := g[u, o, t] = If[u+o == 0, 1, Sum[g[o + j - 1, u - j, 2], {j, 1, u}] + If[tJean-François Alcover, Aug 18 2018, after Alois P. Heinz *)

A230131 Number of permutations of order n with the length of longest run equal 8.

Original entry on oeis.org

2, 32, 462, 6644, 98472, 1523808, 24744720, 422335056, 7575963254, 142706934722, 2819192544786, 58323311592602, 1261634626792744, 28492765388656632, 670804322638496378, 16439609940896532018, 418816100433422180196, 11077009292500273732470
Offset: 8

Views

Author

Alois P. Heinz, Oct 10 2013

Keywords

Crossrefs

Column l=8 of A211318.
A diagonal of A010026.

Programs

  • Maple
    g:= proc(u, o, t) option remember; `if`(u+o=0, 1,
           add(g(o+j-1, u-j, 2), j=1..u) +`if`(t<8,
           add(g(u+j-1, o-j, t+1), j=1..o), 0))
        end:
    b:= proc(u, o, t) option remember; `if`(t=8, g(u, o, t),
           add(b(o+j-1, u-j, 2), j=1..u)+
           add(b(u+j-1, o-j, t+1), j=1..o))
        end:
    a:= n-> add(b(j-1, n-j, 1), j=1..n):
    seq(a(n), n=8..30);
  • Mathematica
    length = 8;
    g[u_, o_, t_] := g[u, o, t] = If[u+o == 0, 1, Sum[g[o + j - 1, u - j, 2], {j, 1, u}] + If[tJean-François Alcover, Aug 18 2018, after Alois P. Heinz *)

A230132 Number of permutations of order n with the length of longest run equal 9.

Original entry on oeis.org

2, 36, 574, 9024, 145080, 2419872, 42129360, 767370240, 14631376500, 291914163322, 6088804487138, 132624737931726, 3012939864521998, 71296697740927172, 1755099895042102380, 44889002698811118240, 1191389820174200208622, 32774409073391657243622
Offset: 9

Views

Author

Alois P. Heinz, Oct 10 2013

Keywords

Crossrefs

Column l=9 of A211318.
A diagonal of A010026.

Programs

  • Maple
    g:= proc(u, o, t) option remember; `if`(u+o=0, 1,
           add(g(o+j-1, u-j, 2), j=1..u) +`if`(t<9,
           add(g(u+j-1, o-j, t+1), j=1..o), 0))
        end:
    b:= proc(u, o, t) option remember; `if`(t=9, g(u, o, t),
           add(b(o+j-1, u-j, 2), j=1..u)+
           add(b(u+j-1, o-j, t+1), j=1..o))
        end:
    a:= n-> add(b(j-1, n-j, 1), j=1..n):
    seq(a(n), n=9..30);
  • Mathematica
    length = 9;
    g[u_, o_, t_] := g[u, o, t] = If[u+o == 0, 1, Sum[g[o + j - 1, u - j, 2], {j, 1, u}] + If[tJean-François Alcover, Aug 18 2018, after Alois P. Heinz *)

A230133 Number of permutations of order n with the length of longest run equal 10.

Original entry on oeis.org

2, 40, 698, 11908, 206388, 3690960, 68577600, 1327697280, 26812356480, 564796979240, 12403183337690, 283718956204402, 6753363090218970, 167092903876164794, 4292602805804464576, 114374394103260000000, 3157276569203744863200, 90202107365906127228000
Offset: 10

Views

Author

Alois P. Heinz, Oct 10 2013

Keywords

Crossrefs

Column l=10 of A211318.
A diagonal of A010026.

Programs

  • Maple
    g:= proc(u, o, t) option remember; `if`(u+o=0, 1,
           add(g(o+j-1, u-j, 2), j=1..u) +`if`(t<10,
           add(g(u+j-1, o-j, t+1), j=1..o), 0))
        end:
    b:= proc(u, o, t) option remember; `if`(t=10, g(u, o, t),
           add(b(o+j-1, u-j, 2), j=1..u)+
           add(b(u+j-1, o-j, t+1), j=1..o))
        end:
    a:= n-> add(b(j-1, n-j, 1), j=1..n):
    seq(a(n), n=10..30);
  • Mathematica
    length = 10;
    g[u_, o_, t_] := g[u, o, t] = If[u+o == 0, 1, Sum[g[o + j - 1, u - j, 2], {j, 1, u}] + If[tJean-François Alcover, Aug 18 2018, after Alois P. Heinz *)
Previous Showing 11-15 of 15 results.