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A362996
Triangle read by rows. T(n, k) = numerator([x^k] R(n, n, x)), where R(n, k, x) = Sum_{u=0..k} ( Sum_{j=0..u} x^j * binomial(u, j) * (j + 1)^n ) / (u + 1).
2
1, 3, 1, 11, 14, 3, 25, 46, 117, 16, 137, 652, 3699, 1344, 125, 49, 568, 19197, 41728, 19375, 1296, 363, 9872, 621837, 2397184, 2084375, 334368, 16807, 761, 23664, 5338467, 17115136, 99109375, 7150032, 6705993, 262144
OFFSET
0,2
FORMULA
T(n, k) = A362995(n, k) * A362997(n, k) / lcm(1, 2, ..., n+1).
EXAMPLE
The triangle T(n, k) begins:
[0] 1;
[1] 3, 1;
[2] 11, 14, 3;
[3] 25, 46, 117, 16;
[4] 137, 652, 3699, 1344, 125;
[5] 49, 568, 19197, 41728, 19375, 1296;
[6] 363, 9872, 621837, 2397184, 2084375, 334368, 16807;
[7] 761, 23664, 5338467, 17115136, 99109375, 7150032, 6705993, 262144;
.
The first few polynomials are:
[0] 1
[1] x + 3/2
[2] 3*x^2 + (14/3)*x + 11/6
[3] 16*x^3 + (117/4)*x^2 + (46/3)*x + 25/12
[4] 125*x^4 + (1344/5)*x^3 + (3699/20)*x^2 + (652/15)*x + 137/60
[5] 1296*x^5 + (19375/6)*x^4 + (41728/15)*x^3 + (19197/20)*x^2 + (568/5)*x + 49/20
PROG
(SageMath)
def R(n, k, x):
return add((1 / (u + 1)) * add(x^j * binomial(u, j) * (j + 1)^n
for j in (0..u)) for u in (0..k))
def A362996row(n: int) -> list[int]:
return [r.numerator() for r in R(n, n, x).list()]
for n in (0..7): print(A362996row(n))
CROSSREFS
Cf. A362997 (denominator), A001008 (column 0), A000272 (main diagonal), A362995.
Sequence in context: A199577 A228534 A119908 * A153257 A002185 A002589
KEYWORD
nonn,tabl,frac
AUTHOR
Peter Luschny, May 13 2023
STATUS
approved