OFFSET
1,2
COMMENTS
See A374848 for the definition of obverse convolution and a guide to related sequences and arrays.
EXAMPLE
First 3 polynomials in s(x)**t(x) are
1 + 2x,
1 + 5 x + 6 x^2,
1 + 11 x + 36 x^2 + 36 x^3.
First 5 rows of array:
1 2
1 5 6
1 11 36 36
1 22 157 432 396
1 40 553 3258 8172 7128
MATHEMATICA
s[n_] := n^2 x; t[n_] := 1 + 2 x;
u[n_] := Product[s[k] + t[n - k], {k, 0, n}]
Table[Expand[u[n]], {n, 0, 10}]
Column[Table[CoefficientList[Expand[u[n]], x], {n, 0, 10}]] (* array *)
Flatten[Table[CoefficientList[Expand[u[n]], x], {n, 0, 10}]] (* sequence *)
CROSSREFS
KEYWORD
nonn,tabf
AUTHOR
Clark Kimberling, Sep 11 2024
STATUS
approved