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A215521
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Number T(n,k) of distinct values of multinomial coefficients M(n;lambda), where lambda ranges over all partitions of n with largest part = k; triangle T(n,k), n>=1, 1<=k<=n, read by rows.
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3
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1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 2, 1, 1, 1, 3, 3, 2, 1, 1, 1, 3, 4, 3, 2, 1, 1, 1, 4, 5, 5, 3, 2, 1, 1, 1, 4, 7, 6, 5, 3, 2, 1, 1, 1, 5, 8, 9, 7, 5, 3, 2, 1, 1, 1, 5, 10, 10, 10, 7, 5, 3, 2, 1, 1, 1, 6, 12, 14, 12, 11, 7, 5, 3, 2, 1, 1, 1, 6, 14, 16, 17, 13, 11, 7, 5, 3, 2, 1, 1
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OFFSET
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1,8
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COMMENTS
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Differs from A008284 first at T(11,4).
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LINKS
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EXAMPLE
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T(4,2) = 2 = |{4!/(2!*2!), 4!/(2!*1!*1!)}| = |{6, 12}|.
T(7,4) = 3 = |{35, 105, 210}|.
T(8,3) = 5 = |{560, 1120, 1680, 3360, 6720}|.
T(11,4) = 10 = |{11550, 34650, 46200, 69300, 138600, 207900, 277200, 415800, 831600, 1663200}|.
Triangle T(n,k) begins:
1;
1, 1;
1, 1, 1;
1, 2, 1, 1;
1, 2, 2, 1, 1;
1, 3, 3, 2, 1, 1;
1, 3, 4, 3, 2, 1, 1;
1, 4, 5, 5, 3, 2, 1, 1;
1, 4, 7, 6, 5, 3, 2, 1, 1;
1, 5, 8, 9, 7, 5, 3, 2, 1, 1;
1, 5, 10, 10, 10, 7, 5, 3, 2, 1, 1;
...
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MAPLE
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b:= proc(n, i) option remember; `if`(n=0, {1}, `if`(i<1, {},
{b(n, i-1)[], seq(map(x-> x*i!^j, b(n-i*j, i-1))[], j=1..n/i)}))
end:
T:= (n, k)-> nops(b(n-k, min(k, n-k))):
seq(seq(T(n, k), k=1..n), n=1..15);
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MATHEMATICA
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b[n_, i_] := b[n, i] = If[n == 0, {1}, If[i < 1, {}, Join[b[n, i - 1], Table[ b[n - i*j, i - 1] *i!^j, {j, 1, n/i}] // Flatten]] // Union]; T[n_, k_] := Length[b[n, k]]; Table[Table[T[n - k, Min[k, n - k]], {k, 1, n}], {n, 1, 15}] // Flatten (* Jean-François Alcover, Jan 21 2015, after Alois P. Heinz *)
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CROSSREFS
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KEYWORD
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AUTHOR
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STATUS
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approved
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