A326322
Square array A(n,k), n>=0, k>=0, read by antidiagonals: A(n,k) = sum of the k-th powers of multinomials M(n; mu), where mu ranges over all compositions of n.
Original entry on oeis.org
1, 1, 1, 1, 1, 2, 1, 1, 3, 4, 1, 1, 5, 13, 8, 1, 1, 9, 55, 75, 16, 1, 1, 17, 271, 1077, 541, 32, 1, 1, 33, 1459, 19353, 32951, 4683, 64, 1, 1, 65, 8263, 395793, 2699251, 1451723, 47293, 128, 1, 1, 129, 48115, 8718945, 262131251, 650553183, 87054773, 545835, 256
Offset: 0
A(2,2) = M(2; 2)^2 + M(2; 1,1)^2 = 1 + 4 = 5.
Square array A(n,k) begins:
1, 1, 1, 1, 1, 1, ...
1, 1, 1, 1, 1, 1, ...
2, 3, 5, 9, 17, 33, ...
4, 13, 55, 271, 1459, 8263, ...
8, 75, 1077, 19353, 395793, 8718945, ...
16, 541, 32951, 2699251, 262131251, 28076306251, ...
- R. P. Stanley, Enumerative Combinatorics, Vol. I, second edition, Example 3.18.3d page 322.
-
b:= proc(n, k) option remember; `if`(n=0, 1,
add(b(n-i, k)/i!^k, i=1..n))
end:
A:= (n, k)-> n!^k*b(n, k):
seq(seq(A(n, d-n), n=0..d), d=0..12);
# second Maple program:
A:= proc(n, k) option remember; `if`(n=0, 1,
add(binomial(n, j)^k*A(j, k), j=0..n-1))
end:
seq(seq(A(n, d-n), n=0..d), d=0..12);
-
A[n_, k_] := A[n, k] = If[n==0, 1, Sum[Binomial[n, j]^k A[j, k], {j, 0, n-1}]];
Table[Table[A[n, d - n], {n, 0, d}], {d, 0, 12}] // Flatten (* Jean-François Alcover, Dec 03 2020, after 2nd Maple program *)
A215910
a(n) = sum of the n-th power of the multinomial coefficients in row n of triangle A036038.
Original entry on oeis.org
1, 1, 5, 244, 354065, 25688403126, 141528428949437282, 83257152559805973052807833, 7012360438832401192319979008881500417, 109324223115831487504443410090345278639832867784010, 396327911646787133737309113762487915762995734538047874429637296650
Offset: 0
The sums of the n-th power of multinomial coefficients in row n of triangle A036038 begin:
a(1) = 1^1 = 1;
a(2) = 1^2 + 2^2 = 5;
a(3) = 1^3 + 3^3 + 6^3 = 244;
a(4) = 1^4 + 4^4 + 6^4 + 12^4 + 24^4 = 354065;
a(5) = 1^5 + 5^5 + 10^5 + 20^5 + 30^5 + 60^5 + 120^5 = 25688403126;
a(6) = 1^6 + 6^6 + 15^6 + 20^6 + 30^6 + 60^6 + 90^6 + 120^6 + 180^6 + 360^6 + 720^6 = 141528428949437282;
a(7) = 1^7 + 7^7 + 21^7 + 35^7 + 42^7 + 105^7 + 140^7 + 210^7 + 210^7 + 420^7 + 630^7 + 840^7 + 1260^7 + 2520^7 + 5040^7 = 83257152559805973052807833; ...
which also form a logarithmic generating function of an integer series:
L(x) = x + 5*x^2/2 + 244*x^3/3 + 354065*x^4/4 + 25688403126*x^5/5 +...
where
exp(L(x)) = 1 + x + 3*x^2 + 84*x^3 + 88602*x^4 + 5137769389*x^5 +...+ A215911(n)*x^n +...
-
b:= proc(n, i, k) option remember; `if`(n=0 or i=1, 1,
b(n-i, min(n-i, i), k)/i!^k+b(n, i-1, k))
end:
a:= n-> n!^n*b(n$3):
seq(a(n), n=0..12); # Alois P. Heinz, Sep 11 2019
-
b[n_, i_, k_] := b[n, i, k] = If[n == 0 || i == 1, 1, b[n - i, Min[n - i, i], k]/i!^k + b[n, i - 1, k]];
a[n_] := n!^n b[n, n, n];
a /@ Range[0, 12] (* Jean-François Alcover, Nov 01 2020, after Alois P. Heinz *)
-
{a(n)=n!^n*polcoeff(1/prod(m=1, n, 1-x^m/m!^n +x*O(x^n)), n)}
for(n=1,15,print1(a(n),", "))
A336437
a(n) = (n!)^n * [x^n] -log(1 - Sum_{k>=1} x^k / (k!)^n).
Original entry on oeis.org
0, 1, 3, 100, 104585, 5781843126, 25450069471437282, 12456703705462747095073458, 900677059707267544414220026068619393, 12337778954350678368447638232258657486399628887370, 39982077640755835496555968029419604779794754953051698069276656138
Offset: 0
-
Table[(n!)^n SeriesCoefficient[-Log[1 - Sum[x^k/(k!)^n, {k, 1, n}]], {x, 0, n}], {n, 0, 10}]
b[n_, k_] := If[n == 0, 0, 1 + (1/n) Sum[Binomial[n, j]^k j b[j, k], {j, 1, n - 1}]]; a[n_] := b[n, n]; Table[a[n], {n, 0, 10}]
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