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A362885
Array read by ascending antidiagonals: A(n, k) = (1 + 2*n)*k^n.
1
1, 0, 1, 0, 3, 1, 0, 5, 6, 1, 0, 7, 20, 9, 1, 0, 9, 56, 45, 12, 1, 0, 11, 144, 189, 80, 15, 1, 0, 13, 352, 729, 448, 125, 18, 1, 0, 15, 832, 2673, 2304, 875, 180, 21, 1, 0, 17, 1920, 9477, 11264, 5625, 1512, 245, 24, 1, 0, 19, 4352, 32805, 53248, 34375, 11664, 2401, 320, 27, 1
OFFSET
0,5
FORMULA
A(n, k) = A005408(n)*A004248(n, k).
O.g.f. of column k: (1 + k*x)/(1 - k*x)^2.
E.g.f. of column k: exp(k*x)*(1 + 2*k*x).
A(n, n) = A176043(n+1).
EXAMPLE
The array begins:
1, 1, 1, 1, 1, 1, ...
0, 3, 6, 9, 12, 15, ...
0, 5, 20, 45, 80, 125, ...
0, 7, 56, 189, 448, 875, ...
0, 9, 144, 729, 2304, 5625, ...
0, 11, 352, 2673, 11264, 34375, ...
...
MATHEMATICA
A[n_, k_]:=(1+2n)k^n; Join[{1}, Table[A[n-k, k], {n, 10}, {k, 0, n}]]//Flatten (* or *)
A[n_, k_]:=SeriesCoefficient[(1+k*x)/(1-k*x)^2, {x, 0, n}]; Table[A[n-k, k], {n, 0, 10}, {k, 0, n}]//Flatten (* or *)
A[n_, k_]:=n!SeriesCoefficient[Exp[k*x](1+2k*x), {x, 0, n}]; Table[A[n-k, k], {n, 0, 10}, {k, 0, n}]//Flatten
CROSSREFS
Cf. A000007 (k=0), A000012 (n=0), A004248, A005408 (k=1), A008585 (n=1), A014480 (k=2), A033429 (n=2), A058962 (k=4), A124647 (k=3), A155988 (k=9), A171220 (k=5), A176043, A199299 (k=6), A199300 (k=7), A199301 (k=8), A244727 (n=3), A362886 (antidiagonal sums).
Sequence in context: A347924 A341103 A021326 * A227342 A329989 A110032
KEYWORD
nonn,tabl
AUTHOR
Stefano Spezia, May 08 2023
STATUS
approved