A246106
Number A(n,k) of inequivalent n X n matrices with entries from [k], where equivalence means permutations of rows or columns; square array A(n,k), n>=0, k>=0, read by antidiagonals.
Original entry on oeis.org
1, 1, 0, 1, 1, 0, 1, 2, 1, 0, 1, 3, 7, 1, 0, 1, 4, 27, 36, 1, 0, 1, 5, 76, 738, 317, 1, 0, 1, 6, 175, 8240, 90492, 5624, 1, 0, 1, 7, 351, 57675, 7880456, 64796982, 251610, 1, 0, 1, 8, 637, 289716, 270656150, 79846389608, 302752867740, 33642660, 1, 0
Offset: 0
Square array A(n,k) begins:
1, 1, 1, 1, 1, 1, ...
0, 1, 2, 3, 4, 5, ...
0, 1, 7, 27, 76, 175, ...
0, 1, 36, 738, 8240, 57675, ...
0, 1, 317, 90492, 7880456, 270656150, ...
0, 1, 5624, 64796982, 79846389608, 20834113243925, ...
Columns k = 0-10 give:
A000007,
A000012,
A002724,
A052269,
A052271,
A052272,
A246112,
A246113,
A246114,
A246115,
A246116.
Rows n = 0-10 give:
A000012,
A001477,
A039623,
A058001,
A058002,
A058003,
A058004,
A246108,
A246109,
A246110,
A246111.
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b:= proc(n, i) option remember; `if`(n=0, [[]],
`if`(i<1, [], [b(n, i-1)[], seq(map(p->[p[], [i, j]],
b(n-i*j, i-1))[], j=1..n/i)]))
end:
A:= proc(n, k) option remember; add(add(k^add(add(i[2]*j[2]*
igcd(i[1], j[1]), j=t), i=s) /mul(i[1]^i[2]*i[2]!, i=s)
/mul(i[1]^i[2]*i[2]!, i=t), t=b(n$2)), s=b(n$2))
end:
seq(seq(A(n, d-n), n=0..d), d=0..10);
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A246106(n,k)=A353585(k,n,n) \\ M. F. Hasler, May 01 2022
A242095
Number A(n,k) of inequivalent n X n matrices with entries from [k], where equivalence means permutations of rows or columns or the symbol set; square array A(n,k), n>=0, k>=0, read by antidiagonals.
Original entry on oeis.org
1, 1, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 5, 1, 0, 1, 1, 8, 18, 1, 0, 1, 1, 9, 139, 173, 1, 0, 1, 1, 9, 408, 15412, 2812, 1, 0, 1, 1, 9, 649, 332034, 10805764, 126446, 1, 0, 1, 1, 9, 749, 2283123, 3327329224, 50459685390, 16821330, 1, 0
Offset: 0
A(2,2) = 5:
[1 1] [2 1] [2 2] [2 1] [2 1]
[1 1], [1 1], [1 1], [2 1], [1 2].
Square array A(n,k) begins:
1, 1, 1, 1, 1, 1, ...
0, 1, 1, 1, 1, 1, ...
0, 1, 5, 8, 9, 9, ...
0, 1, 18, 139, 408, 649, ...
0, 1, 173, 15412, 332034, 2283123, ...
0, 1, 2812, 10805764, 3327329224, 173636442196, ...
Columns k=0-10 give:
A000007,
A000012,
A091059,
A091060,
A091061,
A091062,
A246122,
A246123,
A246124,
A246125,
A246126.
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with(numtheory):
b:= proc(n, i) option remember; `if`(n=0, {0}, `if`(i<1, {},
{seq(map(p-> p+j*x^i, b(n-i*j, i-1) )[], j=0..n/i)}))
end:
A:= proc(n, k) option remember; add(add(add(mul(mul(add(d*
coeff(u, x, d), d=divisors(ilcm(i, j)))^(igcd(i, j)*
coeff(s, x, i)*coeff(t, x, j)), j=1..degree(t)),
i=1..degree(s))/mul(i^coeff(u, x, i)*coeff(u, x, i)!,
i=1..degree(u))/mul(i^coeff(t, x, i)*coeff(t, x, i)!,
i=1..degree(t))/mul(i^coeff(s, x, i)*coeff(s, x, i)!,
i=1..degree(s)), u=b(k$2)), t=b(n$2)), s=b(n$2))
end:
seq(seq(A(n, d-n), n=0..d), d=0..10);
-
b[n_, i_] := b[n, i] = If[n==0, {0}, If[i<1, {}, Flatten@Table[Map[ Function[p, p + j*x^i], b[n - i*j, i - 1]], {j, 0, n/i}]]];
A[n_, k_] := A[n, k] = Sum[Sum[Sum[Product[Product[With[{g = GCD[i, j]* Coefficient[s, x, i]*Coefficient[t, x, j]}, If[g == 0, 1, Sum[d* Coefficient[u, x, d], {d, Divisors[LCM[i, j]]}]^g]], {j, Exponent[t, x]} ],
{i, Exponent[s, x]}]/Product[i^Coefficient[u, x, i]*Coefficient[u, x, i]!,
{i, Exponent[u, x]}]/Product[i^Coefficient[t, x, i]*Coefficient[t, x, i]!,
{i, Exponent[t, x]}]/Product[i^Coefficient[s, x, i]*Coefficient[s, x, i]!,
{i, Exponent[s, x]}], {u, b[k, k]}], {t, b[n, n]}], {s, b[n, n]}];
Table[Table[A[n, d - n], {n, 0, d}], {d, 0, 10}] // Flatten (* Jean-François Alcover, Feb 21 2016, after Alois P. Heinz, updated Jan 01 2021 *)
A091057
Number of n X n matrices over symbol set {1,...,n^2} equivalent under any permutation of row, columns or the symbol set.
Original entry on oeis.org
1, 1, 9, 777, 18500104, 322286625959257, 7368376339801908226685191, 422262377369187686156418513093399998333, 105882936532098986759153041871810253870024776751177723954
Offset: 0
-
b[n_, i_] := b[n, i] = If[n == 0, {0}, If[i < 1, {}, Flatten @ Table[Map[Function[p, p + j*x^i], b[n - i*j, i - 1]], {j, 0, n/i}]]];
A242095[n_, k_] := A242095[n, k] = With[{co = Coefficient, ex = Exponent}, Sum[Sum[Sum[Product[Product[With[{g = GCD[i, j]*co[s, x, i]*co[t, x, j]}, If[g == 0, 1, Sum[d*co[u, x, d], {d, Divisors[LCM[i, j]]}]^g]], {j, ex[t, x]}], {i, ex[s, x]}]/Product[i^co[u, x, i]*co[u, x, i]!, {i, ex[u, x]}]/Product[i^co[t, x, i]*co[t, x, i]!, {i, ex[t, x]}]/Product[i^co[s, x, i]*co[s, x, i]!, {i, ex[s, x]}], {u, b[k, k]}], {t, b[n, n]}], {s, b[n, n]}]];
a[n_] := A242095[n, n^2];
Table[Print[n, " ", a[n]]; a[n], {n, 0, 6}] (* Jean-François Alcover, May 29 2023, after Alois P. Heinz in A242095 *)
A360664
Number of inequivalent n X n matrices using exactly n different symbols, where equivalence means permutations of rows or columns or the symbol set.
Original entry on oeis.org
1, 1, 4, 121, 316622, 170309112972, 27417944542834007012, 1999576637456562016308833727820, 95614444589289128555388037722252407519896044, 4112190260012069813083100063825969898935642267505877920574871
Offset: 0
a(2) = 4:
[1 0] [1 1] [1 0] [1 0]
[0 0], [0 0], [1 0], [0 1].
Showing 1-4 of 4 results.
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