|
Search: id:A019448
|
|
|
| A019448 |
|
Number of monomials in expansion of determinant of an n X n Hankel matrix [ t(i+j) ] in terms of its entries. |
|
+0
2
|
|
| 1, 2, 5, 16, 58, 231, 1016, 4782, 23653, 121727, 648611
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
FORMULA
|
with(linalg): A019448 := proc(n) local i, j, m; m := array(1..n, 1..n); for i from 1 to n do for j from 1 to n do m[i, j] := a[i+j] od od; nops([coeffs(det(m))]); end;
|
|
MATHEMATICA
|
f[n_] := Length@ Expand@ Det@ Table[t[i + j], {i, n}, {j, n}]; Do[ Print@ f@n, {n, 11}] - from Robert G. Wilson v Sep 17 2006
|
|
CROSSREFS
|
Adjacent sequences: A019445 A019446 A019447 this_sequence A019449 A019450 A019451
Sequence in context: A114296 A121689 A009225 this_sequence A000753 A007878 A019589
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Herbert Wilf (wilf(AT)central.cis.upenn.edu)
|
|
EXTENSIONS
|
Maple program and 2 more terms from Jeffrey Shallit (shallit(AT)graceland.uwaterloo.ca), Jun 08 2000
a(10) and a(11) from Robert G. Wilson v Sep 17 2006
|
|
|
Search completed in 0.002 seconds
|
