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A259841
Number T(n,k) of elements k in all n X n Tesler matrices of nonnegative integers; triangle T(n,k), n>=1, 1<=k<=n, read by rows.
5
1, 3, 1, 15, 5, 2, 117, 37, 17, 7, 1367, 418, 189, 100, 40, 23329, 7027, 3058, 1688, 939, 357, 570933, 171428, 72194, 39274, 24050, 13429, 4820, 19740068, 5948380, 2449366, 1293768, 807576, 517548, 283510, 96030
OFFSET
1,2
COMMENTS
For the definition of Tesler matrices see A008608.
Sum_{k=1..n} k * T(n,k) = A259787(n).
LINKS
EXAMPLE
There are two 2 X 2 Tesler matrices: [1,0; 0,1], [0,1; 0,2], containing three 1's and one 2, thus row 2 gives [3, 1].
Triangle T(n,k) begins:
1;
3, 1;
15, 5, 2;
117, 37, 17, 7;
1367, 418, 189, 100, 40;
23329, 7027, 3058, 1688, 939, 357;
570933, 171428, 72194, 39274, 24050, 13429, 4820;
...
MAPLE
g:= u-> `if`(u=0, 0, x^u):
b:= proc(n, i, l) option remember; (m->`if`(m=0, [1, g(n)], `if`(i=0,
(p->p+[0, p[1]*g(n)])(b(l[1]+1, m-1, subsop(1=NULL, l))), add(
(p->p+[0, p[1]*g(j)])(b(n-j, i-1, subsop(i=l[i]+j, l)))
, j=0..n))))(nops(l))
end:
T:= n-> (p-> seq(coeff(p, x, i), i=1..n))(b(1, n-1, [0$(n-1)])[2]):
seq(T(n), n=1..10);
MATHEMATICA
g[u_] := If[u == 0, 0, x^u];
b[n_, i_, l_] := b[n, i, l] = Function[m, If[m == 0, {1, g[n]}, If[i == 0, # + {0, #[[1]] g[n]} & [b[l[[1]]+1, m-1, ReplacePart[l, 1 -> Nothing]]], Sum[# + {0, #[[1]] g[j]} & [b[n-j, i-1, ReplacePart[l, i -> l[[i]] + j]]], {j, 0, n}]]]][Length[l]];
T[n_] := Table[Coefficient[#, x, i], {i, 1, n}] & [b[1, n-1, Table[0, {n-1}]][[2]]];
Array[T, 10] // Flatten (* Jean-François Alcover, Oct 28 2020, after Maple *)
CROSSREFS
Main diagonal gives A008608(n-1) for n>1.
Column k=1 gives A259843.
Row sums give A259842.
Cf. A259787.
Sequence in context: A121335 A126454 A293558 * A228540 A144815 A065250
KEYWORD
nonn,tabl
AUTHOR
Alois P. Heinz, Jul 06 2015
STATUS
approved