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 21-30 of 38 results. Next

A060246 Triangle whose rows are the degrees of the irreducible representations of the groups PSL(2,p) as p runs through the primes.

Original entry on oeis.org

1, 1, 2, 1, 1, 1, 3, 1, 3, 3, 4, 5, 1, 3, 3, 6, 7, 8, 1, 5, 5, 10, 10, 11, 12, 12, 1, 7, 7, 12, 12, 12, 13, 14, 14, 1, 9, 9, 16, 16, 16, 16, 17, 18, 18, 18, 1, 9, 9, 18, 18, 18, 18, 19, 20, 20, 20, 20, 1, 11, 11, 22, 22, 22, 22, 22, 23, 24, 24, 24, 24, 24, 1, 15, 15, 28, 28, 28, 28, 28
Offset: 1

Views

Author

N. J. A. Sloane, Mar 22 2001

Keywords

Examples

			1,1,2; 1,1,1,3; 1,3,3,4,5; ... (for q=2,3,5,...).
		

References

  • J. H. Conway, R. T. Curtis, S. P. Norton, R. A. Parker and R. A. Wilson, ATLAS of Finite Groups, Oxford Univ. Press, 1985.

Crossrefs

Row length sequence is A124678.
Consecutive row sequences from 3rd to 11th are: A003860, A003879, A003882, A003883, A003885, A003886, A003887, A003890, A003891.

Programs

  • Magma
    CharacterTable(PSL(2,7)); (say)
    
  • Magma
    &cat[[Degree(irred): irred in CharacterTable(PSL(2, p))]: p in PrimesUpTo(30)];

Extensions

Extended by Jason Kimberley, May 23 2010

A089248 a(n) is the sum of the odd degrees of the irreducible representations of the symmetric group S_n.

Original entry on oeis.org

1, 2, 2, 8, 12, 40, 144, 128, 644, 3504, 7000, 48224, 130992, 861792, 3257600, 32768, 425988, 5833312, 27621672, 415526656, 1987852432, 17674429440, 157807273408, 265515959680, 2848581615344, 30980959604096, 114059874705248, 1365388896050048, 6215927122198944
Offset: 1

Views

Author

Yuval Dekel (dekelyuval(AT)hotmail.com), Dec 11 2003

Keywords

Comments

a(n) is divisible by 4 for n >= 4. - Eric M. Schmidt, Apr 28 2013

References

  • John McKay, Irreducible representations of odd degree, Journal of Algebra 20, 1972 pages 416-418.

Crossrefs

Programs

  • Mathematica
    h[l_] := With[{n = Length[l]}, Total[l]!/Product[Product[1 + l[[i]] - j + Sum[If[l[[k]] >= j, 1, 0], {k, i + 1, n}], {j, 1, l[[i]]}], {i, 1, n}]];
    g[n_, i_, l_] := If[n == 0 || i == 1, h[Join[l, Array[1 &, n]]], If[i < 1, 0, Flatten@ Table[g[n - i*j, i - 1, Join[l, Array[i &, j]]], {j, 0, n/i}]]];
    a[n_] := a[n] = If[n == 1, 1, Select[g[n, n, {}], OddQ] // Total];
    Table[Print[n, " ", a[n]];
    a[n], {n, 1, 50}] (* Jean-François Alcover, Sep 23 2024, after Alois P. Heinz in A060240 *)
  • Sage
    # Simple but inefficient; see links for faster code
    def A089248(n) :
        res = 0
        for P in Partitions(n) :
            deg = P.dimension()
            if is_odd(deg) : res += deg
        return res
    # Eric M. Schmidt, Apr 28 2013

Formula

a(2^n) = 2^(2^n - 1). - Eric M. Schmidt, Apr 28 2013

Extensions

More terms from Eric M. Schmidt, Apr 28 2013

A104707 Triangle read by rows distributing the 1602 multinomials described by A005651(6) related to Young tableau and Kostka numbers.

Original entry on oeis.org

1, 25, 1, 81, 20, 1, 25, 54, 15, 1, 100, 15, 36, 15, 1, 256, 60, 10, 27, 10, 1, 25, 128, 30, 5, 27, 10, 1, 100, 10, 64, 30, 5, 18, 10, 1, 81, 40, 5, 32, 10, 5, 9, 5, 1, 25, 27, 10, 0, 32, 10, 0, 9, 5, 1, 1, 5, 9, 10, 5, 16, 10, 5, 9, 5, 1
Offset: 1

Views

Author

Alford Arnold, Mar 19 2005

Keywords

Comments

The last row (and the square roots of the first column) is 1 5 9 5 10 16 5 10 9 5 1, which when sorted appears as 1 1 5 5 5 5 9 9 10 10 16 in A003870 and A060240. The 1602 cases are distributed in A036038: 1 6 15 20 30 60 90 120 180 360 720.

Examples

			The triangle is:
1;
25,   1;
81,  20,  1;
25,  54, 15,  1;
100, 15, 36, 15,  1;
256, 60, 10, 27, 10,  1;
25, 128, 30,  5, 27, 10,  1;
100, 10, 64, 30,  5, 18, 10, 1;
81,  40,  5, 32, 10,  5,  9, 5, 1;
25,  27, 10,  0, 32, 10,  0, 9, 5, 1;
1,    5,  9, 10,  5, 16, 10, 5, 9, 5, 1;
		

References

  • D. Stanton and D. White, Constructive Combinatorics, 1986, page 83.

Crossrefs

Cf. A000041, A000085, A000142, A003870, A060240, A005651, A036038 and A097522 (a similar triangle distributing the 246 multinomials in A005651(5)).
Cf. A104778.

A060369 a(n) is the maximum number of occurrences of a degree in the sequence of the degrees of the irreducible representations of the symmetric group S_n.

Original entry on oeis.org

1, 2, 2, 2, 2, 4, 4, 2, 3, 2, 4, 4, 6, 6, 6, 4, 8, 6, 10, 6, 8, 8, 12, 8, 12, 12, 10, 12, 22, 14, 12, 12, 16, 18, 30, 14, 20, 26, 16, 20, 22, 20, 26, 25, 24, 24, 32, 16, 32, 30, 26, 24, 32, 32, 40, 32, 34, 32, 32, 34, 44, 30, 44, 36, 52, 34, 54, 38, 56, 50
Offset: 1

Views

Author

Avi Peretz (njk(AT)netvision.net.il), Apr 01 2001

Keywords

Examples

			a(6) = 4 because the degrees for S_6 are 1,1,5,5,5,5,9,9,10,10,16 and the number 5 appears 4 times.
		

Programs

  • Mathematica
    h[l_] := With[{n = Length[l]}, Total[l]!/Product[Product[1 + l[[i]] - j + Sum[If[l[[k]] >= j, 1, 0], {k, i + 1, n}], {j, 1, l[[i]]}], {i, 1, n}]];
    g[n_, i_, l_] := If[n == 0 || i == 1, h[Join[l, Array[1&, n]]], If[i < 1, 0, Flatten@ Table[g[n - i*j, i - 1, Join[l, Array[i&, j]]], {j, 0, n/i}]]];
    a[n_] := a[n] = If[n == 1, 1, MaximalBy[Tally[g[n, n, {}]], Last][[1, 2]]];
    Table[Print[n, " ", a[n]];
    a[n], {n, 1, 50}] (* Jean-François Alcover, Sep 23 2024, after Alois P. Heinz in A060240 *)
  • Sage
    def A060369(n) :
        mult = {}
        for P in Partitions(n):
            dim = P.dimension()
            mult[dim] = mult.get(dim, 0) + 1
        return max(mult.values())
    # Eric M. Schmidt, May 01 2013

Extensions

More terms from Eric M. Schmidt, May 01 2013

A060426 a(n) is the number of degrees in the sequence of the degrees of the irreducible representations of the symmetric group S_n that appear only once.

Original entry on oeis.org

1, 0, 1, 1, 1, 1, 1, 2, 1, 2, 2, 3, 2, 3, 4, 4, 5, 5, 4, 6, 8, 8, 6, 7, 10, 11, 11, 15, 15, 16, 18, 21, 22, 23, 29, 33, 31, 31, 39, 43, 44, 52, 51, 58, 64, 71, 66, 82, 88, 96, 93, 103, 115, 128, 143, 150, 156, 160, 173, 199, 202, 202, 242, 263, 269, 293, 308
Offset: 1

Views

Author

Avi Peretz (njk(AT)netvision.net.il), Apr 05 2001

Keywords

Comments

Bounded above by A000700(n). - Eric M. Schmidt, Apr 29 2013

Examples

			a(6) = 1 because the degrees for S_6 are 1,1,5,5,5,5,9,9,10,10,16 and the only number that appears once is 16.
		

Crossrefs

Cf. A059867, A060368, A060369, A060437, A061569, A089248. [From M. F. Hasler, Jun 14 2009]

Programs

  • Mathematica
    h[l_] := With[{n = Length[l]}, Total[l]!/Product[Product[1 + l[[i]] - j + Sum[If[l[[k]] >= j, 1, 0], {k, i + 1, n}], {j, 1, l[[i]]}], {i, 1, n}]];
    g[n_, i_, l_] := If[n == 0 || i == 1, h[Join[l, Array[1&, n]]], If[i < 1, 0, Flatten@ Table[g[n - i*j, i - 1, Join[l, Array[i&, j]]], {j, 0, n/i}]]];
    a[n_] := a[n] = If[n == 1, 1, Count[Tally[g[n, n, {}]], {_, 1}] ];
    Table[Print[n, " ", a[n]]; a[n], {n, 1, 50}] (* Jean-François Alcover, Sep 23 2024, after Alois P. Heinz in A060240 *)
  • Sage
    def A060426(n) :
        mult = {}
        for P in Partitions(n) :
            dim = P.dimension()
            mult[dim] = mult.get(dim, 0) + 1
        return len([m for m in iter(mult) if mult[m]==1])
    # Eric M. Schmidt, Apr 29 2013

Extensions

More terms from Eric M. Schmidt, Apr 29 2013

A117500 Triangle read by rows in which row n gives the partition of n associated with highest degree representation of symmetric group S_n.

Original entry on oeis.org

1, 2, 2, 1, 3, 1, 3, 1, 1, 3, 2, 1, 4, 2, 1, 4, 2, 1, 1, 4, 3, 1, 1, 4, 3, 2, 1, 5, 3, 2, 1, 5, 3, 2, 1, 1, 5, 4, 2, 1, 1, 6, 4, 2, 1, 1, 5, 4, 3, 2, 1, 6, 4, 3, 2, 1, 6, 4, 3, 2, 1, 1, 7, 4, 3, 2, 1, 1, 7, 5, 3, 2, 1, 1, 7, 5, 3, 2, 2, 1, 7, 5, 3, 2, 2, 1, 1, 7, 5, 4, 3, 2, 1, 7, 5, 4, 3, 2, 1
Offset: 1

Views

Author

N. J. A. Sloane, Apr 28 2006

Keywords

Comments

Note that a partition and its conjugate give the same degree representation of the symmetric group. We take the lexicographically earlier of the two.

Examples

			Triangle begins:
1
2
2 1
3 1
3 1 1
3 2 1
4 2 1
4 2 1 1
4 3 1 1
4 3 2 1
5 3 2 1
5 3 2 1 1
5 4 2 1 1
6 4 2 1 1
5 4 3 2 1
6 4 3 2 1
6 4 3 2 1 1
7 4 3 2 1 1
7 5 3 2 1 1
7 5 3 2 2 1
7 5 3 2 2 1 1
7 5 4 3 2 1
7 5 4 3 2 1 1
8 5 4 3 2 1 1
8 6 4 3 2 1 1
		

Crossrefs

See A003040 for much more information. Cf. A060240.

Formula

If p_1 >= p_2 >= ... >= p_k is the partition of n, the degree of the representation (given in A003040) is n! * Product_{i

A224653 Irregular table which shows in row n the dimensions of the irreducible representations of the permutation group of order n!.

Original entry on oeis.org

1, 1, 1, 1, 2, 1, 2, 3, 1, 4, 5, 6, 1, 5, 9, 10, 16, 1, 6, 14, 15, 20, 21, 35, 1, 7, 14, 20, 21, 28, 35, 42, 56, 64, 70, 90, 1, 8, 27, 28, 42, 48, 56, 70, 84, 105, 120, 162, 168, 189, 216, 1, 9, 35, 36, 42, 75, 84, 90, 126, 160, 210, 225, 252, 288, 300, 315, 350, 448, 450, 525, 567, 768
Offset: 0

Author

R. J. Mathar, May 09 2013

Keywords

Comments

This is triangle A060240 if duplicates in individual rows are removed.
The entries in row n give the number of standard Young tableaux of the Ferrers diagrams of the partitions of n (without duplicates, increasingly). Example: n = 4; there are 5 partitions of 4: [4], [3,1], [2,2], [2,1,1], and [1,1,1,1]; their Ferrers graphs have 1, 3, 2, 3, and 1 standard tableaux, respectively. - Emeric Deutsch, May 26 2015

Examples

			The group of permutations of [8] has 2 representations of dimension 1, 2 of dimension 7, 2 of dimension 14, 2 of dimension 20, 2 of dimension 21, 2 of dimension 28, 2 of dimension 35, 1 of dimension 42, 2 of dimension 56, 2 of dimension 64, 2 of dimension of 70 and 1 of dimension 90.
1;
1;
1;
1,2;
1,2,3;
1,4,5,6;
1,5,9,10,16;
1,6,14,15,20,21,35;
1,7,14,20,21,28,35,42,56,64,70,90;
1,8,27,28,42,48,56,70,84,105,120,162,168,189,216;
1,9,35,36,42,75,84,90,126,160,210,225,252,288,300,315,350,448,450,525,567,768;
		

Crossrefs

Cf. A060240.

Programs

  • Maple
    h:= proc(l) local n; n:= nops(l); add(i, i=l)!/mul(mul(1+l[i]-j+
          add(`if`(l[k]>=j, 1, 0), k=i+1..n), j=1..l[i]), i=1..n) end:
    g:= (n, i, l)-> `if`(n=0 or i=1, h([l[], 1$n]), `if`(i<1, 0,
                     seq(g(n-i*j, i-1, [l[], i$j]), j=0..n/i))):
    T:= n-> sort([{g(n$2, [])}[]])[]:
    seq(T(n), n=0..12);  # Alois P. Heinz, May 26 2015
  • Mathematica
    h[l_List] := Module[{n}, n = Length[l]; Total[l]!/Product[Product[1 + l[[i]] - j + Sum[If[l[[k]] >= j, 1, 0], {k, i+1, n}], {j, 1, l[[i]]}], {i, 1, n}]]; g[n_, i_, l_List] := If[n==0 || i==1, h[Join[l, Array[1&, n]]], If[i<1, 0,Table[g[n - i*j, i-1, Join [l, Array[i&, j]]], {j, 0, n/i}]]]; T[n_] := g[n, n, {}] // Flatten // Union; T[1] = {1}; Table[T[n], {n, 1, 12}] // Flatten (* Jean-François Alcover, Jul 03 2015, after Alois P. Heinz *)

A027842 Number of subgroups of index n in fundamental group of a certain fiber space.

Original entry on oeis.org

1, 7, 34, 227, 1296, 10576, 77554, 729379, 7013419, 77371042, 910455096, 11877617828, 165087132666, 2480783846184, 39677415301224, 675818886754115, 12180498014887816, 231893906693650507, 4645789707491981892, 97740610362119850762, 2153888078209948673032
Offset: 1

Keywords

Crossrefs

Extensions

More terms from Sean A. Irvine, Dec 07 2019

A093716 Hook products of all partitions of 5.

Original entry on oeis.org

20, 24, 24, 30, 30, 120, 120
Offset: 1

Author

Emeric Deutsch, May 17 2004

Keywords

Crossrefs

Row n=5 of A093784.

Programs

  • Maple
    H:=proc(pa) local F,j,p,Q,i,col,a,A: F:=proc(x) local i, ct: ct:=0: for i from 1 to nops(x) do if x[i]>1 then ct:=ct+1 else fi od: ct; end: for j from 1 to nops(pa) do p[1][j]:=pa[j] od: Q[1]:=[seq(p[1][j],j=1..nops(pa))]: for i from 2 to pa[1] do for j from 1 to F(Q[i-1]) do p[i][j]:=Q[i-1][j]-1 od: Q[i]:=[seq(p[i][j],j=1..F(Q[i-1]))] od: for i from 1 to pa[1] do col[i]:=[seq(Q[i][j]+nops(Q[i])-j,j=1..nops(Q[i]))] od: a:=proc(i,j) if i<=nops(Q[j]) and j<=pa[1] then Q[j][i]+nops(Q[j])-i else 1 fi end: A:=matrix(nops(pa),pa[1],a): product(product(A[m,n],n=1..pa[1]),m=1..nops(pa)); end: with(combinat): rev:=proc(a) [seq(a[nops(a)+1-i],i=1..nops(a))] end: sort([seq(H(rev(partition(5)[q])), q=1..numbpart(5))]);
  • Mathematica
    h[l_] := With[{n = Length[l]}, Total[l]!/Product[Product[1 + l[[i]] - j + Sum[If[l[[k]] >= j, 1, 0], {k, i + 1, n}], {j, 1, l[[i]]}], {i, 1, n}]];
    g[n_, i_, l_] := If[n == 0 || i == 1, h[Join[l, Array[1&, n]]], If[i < 1, 0, Flatten@Table[g[n - i*j, i - 1, Join[l, Array[i&, j]]], {j, 0, n/i}]]];
    T[n_] := g[n, n, {}];
    Sort[5!/T[5]] (* Jean-François Alcover, Aug 12 2024, after Alois P. Heinz in A060240 *)

Formula

a(n) = 5!/A003869(8-n).

A093764 Hook products of all partitions of 6.

Original entry on oeis.org

45, 72, 72, 80, 80, 144, 144, 144, 144, 720, 720
Offset: 1

Author

Emeric Deutsch, May 17 2004

Keywords

Crossrefs

Row n=6 of A093784.

Programs

  • Maple
    H:=proc(pa) local F,j,p,Q,i,col,a,A: F:=proc(x) local i, ct: ct:=0: for i from 1 to nops(x) do if x[i]>1 then ct:=ct+1 else fi od: ct; end: for j from 1 to nops(pa) do p[1][j]:=pa[j] od: Q[1]:=[seq(p[1][j],j=1..nops(pa))]: for i from 2 to pa[1] do for j from 1 to F(Q[i-1]) do p[i][j]:=Q[i-1][j]-1 od: Q[i]:=[seq(p[i][j],j=1..F(Q[i-1]))] od: for i from 1 to pa[1] do col[i]:=[seq(Q[i][j]+nops(Q[i])-j,j=1..nops(Q[i]))] od: a:=proc(i,j) if i<=nops(Q[j]) and j<=pa[1] then Q[j][i]+nops(Q[j])-i else 1 fi end: A:=matrix(nops(pa),pa[1],a): product(product(A[m,n],n=1..pa[1]),m=1..nops(pa)); end: with(combinat): rev:=proc(a) [seq(a[nops(a)+1-i],i=1..nops(a))] end: sort([seq(H(rev(partition(6)[q])),q=1..numbpart(6))]);
  • Mathematica
    h[l_] := With[{n = Length[l]}, Total[l]!/Product[Product[1 + l[[i]] - j + Sum[If[l[[k]] >= j, 1, 0], {k, i+1, n}], {j, 1, l[[i]]}], {i, 1, n}]];
    g[n_, i_, l_] := If[n == 0 || i == 1, h[Join[l, Array[1&, n]]], If[i < 1, 0, Flatten@Table[g[n - i*j, i-1, Join[l, Array[i&, j]]], {j, 0, n/i}]]];
    T[n_] := g[n, n, {}];
    Sort[6!/T[6]] (* Jean-François Alcover, Jul 20 2024, after Alois P. Heinz in A060240 *)

Formula

a(n) = 6!/A003870(12-n).
Previous Showing 21-30 of 38 results. Next