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A144393
Triangle read by rows (n >= 0, 0 <= k <= n): row n gives the coefficients in the expansion of x^n + n*x^(n - 1) + n*x + 1.
1
2, 2, 2, 1, 4, 1, 1, 3, 3, 1, 1, 4, 0, 4, 1, 1, 5, 0, 0, 5, 1, 1, 6, 0, 0, 0, 6, 1, 1, 7, 0, 0, 0, 0, 7, 1, 1, 8, 0, 0, 0, 0, 0, 8, 1, 1, 9, 0, 0, 0, 0, 0, 0, 9, 1, 1, 10, 0, 0, 0, 0, 0, 0, 0, 10, 1, 1, 11, 0, 0, 0, 0, 0, 0, 0, 0, 11, 1, 1, 12, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12, 1
OFFSET
0,1
EXAMPLE
Triangle begins:
2;
2, 2;
1, 4, 1;
1, 3, 3, 1;
1, 4, 0, 4, 1;
1, 5, 0, 0, 5, 1;
1, 6, 0, 0, 0, 6, 1;
1, 7, 0, 0, 0, 0, 7, 1;
1, 8, 0, 0, 0, 0, 0, 8, 1;
1, 9, 0, 0, 0, 0, 0, 0, 9, 1;
1, 10, 0, 0, 0, 0, 0, 0, 0, 10, 1;
...
MATHEMATICA
p[x_, n_] = x^n + n*x^(n - 1) + n*x + 1;
Table[CoefficientList[p[x, n], x], {n, 0, 10}] // Flatten
PROG
(Maxima) T(n, k) := ratcoef(x^n + n*x^(n - 1) + n*x + 1, x, k)$
create_list(T(n, k), n, 0, 20, k, 0, n);
/* Franck Maminirina Ramaharo, Jan 25 2019 */
CROSSREFS
Row sums: A005843.
Cf. A144394.
Sequence in context: A350189 A289778 A277523 * A351112 A089400 A239209
KEYWORD
nonn,easy,tabl
AUTHOR
EXTENSIONS
Edited and offset corrected by Franck Maminirina Ramaharo, Jan 25 2019
STATUS
approved