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 1-3 of 3 results.

A065181 Permutation of nonnegative integers produced when the finite permutations listed by A055089 are subjected to inverse of Foata's transformation. Inverse of A065182.

Original entry on oeis.org

0, 1, 2, 5, 3, 4, 6, 7, 14, 23, 17, 20, 8, 11, 12, 22, 13, 21, 9, 10, 16, 18, 15, 19, 24, 25, 26, 29, 27, 28, 54, 55, 86, 119, 95, 110, 62, 71, 78, 116, 79, 113, 65, 68, 92, 102, 89, 103, 30, 31, 38, 47, 41, 44, 48, 49, 84, 118, 94, 108, 50, 53, 80, 117, 83, 109, 51, 52
Offset: 0

Views

Author

Antti Karttunen, Oct 19 2001

Keywords

Comments

Here we use the inverse of the left-right maxima variant of Foata's transformation, which works by rotating each cycle largest element first and then sorts the cycles to ascending order, according to that first (and largest) element of each.

References

  • I.M. Gessel and R. P. Stanley, Algebraic Enumeration, chapter 21 in Handbook of Combinatorics, Vol. 2, edited by R.L.Graham et al., The MIT Press, Mass, 1995, page 1045.

Crossrefs

A065161-A065163 give cycle counts and max lengths. Cf. also A065183, A065184 and A055089 and A056019 for the requisite Maple procedures.

Programs

  • Maple
    [seq(PermRevLexRank(FoataInv(PermRevLexUnrank(j))),j=0..119)];
    with(group); FoataInv := p -> map(op, sort([op(map(RotCycleLargestFirst,convert(p,`disjcyc`))),op(FixedCycles(p))], sortbyfirst));
    sortbyfirst := (a,b) -> `if`((a[1] < b[1]),true,false);
    FindLargest := proc(a) local i,m; m := 0; for i from 1 to nops(a) do if(0 = m) then m := i; else if(a[i] > a[m]) then m := i; fi; fi; od; RETURN(m); end;
    RotCycleLargestFirst := proc(c) local x; x := FindLargest(c); if(x <= 1) then RETURN(c); else RETURN([op(c[x..nops(c)]),op(c[1..(x-1)])]); fi; end;
    FixedCycles := proc(p) local a,i; a := []; for i from 1 to nops(p) do if(p[i] = i) then a := [op(a),[i]]; fi; od; RETURN(a); end;

A065184 Permutation of nonnegative integers produced when the finite permutations listed by A060117 are subjected to the left-right maxima variant of Foata's transformation. Inverse of A065183.

Original entry on oeis.org

0, 1, 2, 5, 3, 4, 6, 7, 14, 23, 15, 22, 8, 21, 12, 16, 19, 11, 17, 10, 9, 13, 20, 18, 24, 25, 26, 29, 27, 28, 54, 55, 86, 119, 87, 118, 56, 117, 84, 88, 115, 59, 89, 58, 57, 85, 116, 114, 30, 31, 80, 107, 81, 106, 48, 49, 60, 67, 61, 66, 74, 92, 38, 113, 47, 101, 112, 100
Offset: 0

Views

Author

Antti Karttunen, Oct 19 2001

Keywords

Crossrefs

A065161-A065163 give cycle counts and max lengths. Cf. also A065181, A065182 for Maple procedure Foata and A060117 for PermUnrank3R and A060125 for PermRank3R.

Programs

  • Maple
    [seq(PermRank3R(Foata(PermUnrank3R(j))),j=0..119)];

A065183 Permutation of nonnegative integers produced when the finite permutations listed by A060117 are subjected to the inverse of (variant of) Foata's transformation. Inverse of A065184.

Original entry on oeis.org

0, 1, 2, 4, 5, 3, 6, 7, 12, 20, 19, 17, 14, 21, 8, 10, 15, 18, 23, 16, 22, 13, 11, 9, 24, 25, 26, 28, 29, 27, 48, 49, 78, 108, 103, 91, 74, 111, 62, 69, 75, 104, 101, 94, 100, 83, 71, 64, 54, 55, 80, 109, 107, 90, 30, 31, 36, 44, 43, 41, 56, 58, 72, 110, 106, 77, 59, 57, 81
Offset: 0

Views

Author

Antti Karttunen, Oct 19 2001

Keywords

Crossrefs

A065161-A065163 give cycle counts and max lengths. Cf. also A065182, A065181 for Maple procedure FoataInv and A060117 for PermUnrank3R and A060125 for PermRank3R.

Programs

  • Maple
    [seq(PermRank3R(FoataInv(PermUnrank3R(j))),j=0..119)];
Showing 1-3 of 3 results.