cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-3 of 3 results.

A362995 Triangle read by rows. T(n, k) = [x^k] lcm({i + 1 : 0 <= i <= n}) * (Sum_{u=0..k} ( Sum_{j=0..u} x^j * binomial(u, j) * (j + 1)^n ) / (u + 1)).

Original entry on oeis.org

1, 3, 2, 11, 28, 18, 25, 184, 351, 192, 137, 2608, 11097, 16128, 7500, 147, 6816, 57591, 166912, 193750, 77760, 1089, 118464, 1865511, 9588736, 20843750, 20062080, 7058940, 2283, 567936, 16015401, 136921088, 495546875, 858003840, 704129265, 220200960
Offset: 0

Views

Author

Peter Luschny, May 14 2023

Keywords

Examples

			Triangle T(n, k) starts:
[0]    1;
[1]    3,      2;
[2]   11,     28,       18;
[3]   25,    184,      351,       192;
[4]  137,   2608,    11097,     16128,      7500;
[5]  147,   6816,    57591,    166912,    193750,     77760;
[6] 1089, 118464,  1865511,   9588736,  20843750,  20062080,   7058940;
[7] 2283, 567936, 16015401, 136921088, 495546875, 858003840, 704129265, 220200960;
		

Crossrefs

Cf. A362993 (row sums), A362994 (alternating row sums), A001008 (column 0), A362992 (main diagonal), A362996/A362997.
Cf. A363000.

Programs

  • Maple
    R := (n, x) -> add(add(x^j*binomial(u, j)*(j + 1)^n, j = 0..u)/(u + 1), u=0..n):
    CoeffList := p -> PolynomialTools:-CoefficientList(p, x):
    poly := (n, x) -> ilcm(seq(i, i = 1..n+1)) * R(n, x):
    seq(print(CoeffList(poly(n, x))), n = 0..7);
  • SageMath
    def A362995row(n: int) -> list[int]:
        s = add((1 / (u + 1)) * add(x^j * binomial(u, j) * (j + 1)^n
            for j in (0..u)) for u in (0..n))
        l = lcm(i + 1 for i in (0..n))
        return (s * l).list()
    for n in (0..7): print(A362995row(n))

Formula

T(n, k) = lcm(1,2, ..., n+1) * A362996(n, k) / A362997(n, k).
Sum_{k=0..n} (-1)^k * T(n, k) = lcm(1,2, ..., n+1) * Bernoulli(n, 1) = A362994(n).

A363154 Triangle read by rows. The Hadamard product of A173018 and A349203.

Original entry on oeis.org

1, 1, 0, 2, 1, 0, 3, 4, 1, 0, 12, 33, 22, 3, 0, 10, 52, 66, 26, 2, 0, 60, 570, 1208, 906, 228, 10, 0, 105, 1800, 5955, 7248, 3573, 600, 15, 0, 280, 8645, 42930, 78095, 62476, 21465, 2470, 35, 0, 252, 14056, 102256, 264702, 312380, 176468, 43824, 3514, 28, 0
Offset: 0

Views

Author

Peter Luschny, May 21 2023

Keywords

Examples

			Triangle T(n, k) starts:
[0]   1;
[1]   1,    0;
[2]   2,    1,     0;
[3]   3,    4,     1,     0;
[4]  12,   33,    22,     3,     0;
[5]  10,   52,    66,    26,     2,     0;
[6]  60,  570,  1208,   906,   228,    10,    0;
[7] 105, 1800,  5955,  7248,  3573,   600,   15,  0;
[8] 280, 8645, 42930, 78095, 62476, 21465, 2470, 35, 0;
		

Crossrefs

Cf. A173018, A349203, A002944 (column 0), A099946, A362994 (alternating row sums), A362990 (row sums).

Programs

  • Maple
    A173018 := (n, k) -> combinat[eulerian1](n, k):
    A349203 := (n, k) -> ilcm(seq(binomial(n, j), j = 0..n)) / binomial(n, k):
    A363154 := (n, k) -> A173018(n, k) * A349203(n, k):
    for n from 0 to 8 do seq(A363154(n, k), k = 0..n) od;

Formula

T(n, k) = A173018(n, k) * A349203(n, k).
Sum_{k=0..n} (-1)^k * T(n, k) = lcm(1, 2, ..., n+1)*Bernoulli(n, 1) = A362994(n).

A362991 Triangle read by rows. T(n, k) = lcm{1, 2, ..., n+1} * Sum_{j=0..n-k} (-1)^(n-k-j) * j! * Stirling2(n - k, j) / (j + k + 1).

Original entry on oeis.org

1, 1, 1, 1, 2, 2, 0, 2, 3, 3, -2, 2, 9, 12, 12, 0, -2, 3, 8, 10, 10, 10, -10, -9, 24, 50, 60, 60, 0, 20, -30, -8, 50, 90, 105, 105, -84, 84, 18, -96, 0, 150, 245, 280, 280, 0, -84, 126, -24, -90, 18, 147, 224, 252, 252, 2100, -2100, 126, 1344, -600, -870, 343, 1568, 2268, 2520, 2520
Offset: 0

Views

Author

Peter Luschny, May 16 2023

Keywords

Comments

A variant of the Akiyama-Tanigawa algorithm for the Bernoulli numbers A164555/ A027642.

Examples

			Triangle T(n, k) starts:
[0]   1;
[1]   1,   1;
[2]   1,   2,   2;
[3]   0,   2,   3,   3;
[4]  -2,   2,   9,  12,  12;
[5]   0,  -2,   3,   8,  10,  10;
[6]  10, -10,  -9,  24,  50,  60,  60;
[7]   0,  20, -30,  -8,  50,  90, 105, 105;
[8] -84,  84,  18, -96,   0, 150, 245, 280, 280;
[9]   0, -84, 126, -24, -90,  18, 147, 224, 252, 252;
		

Crossrefs

Variant: A051714/A051715.
Cf. A362994 (column 0), A002944 (main diagonal), A164555/A027642 (Bernoulli).

Programs

  • Maple
    LCM := n -> ilcm(seq((1 + i), i = 0..n)):
    T := (n, k) -> LCM(n)*add((-1)^(n - k - j)*j!*Stirling2(n - k, j)/(j + k + 1), j = 0..n - k):
    for n from 0 to 9 do seq(T(n, k), k = 0..n) od;
  • Mathematica
    A362991row[n_]:=Table[LCM@@Range[n+1]Sum[(-1)^(n-k-j)j!StirlingS2[n-k,j]/(j+k+1),{j,0,n-k}],{k,0,n}];Array[A362991row,15,0] (* Paolo Xausa, Aug 09 2023 *)
  • SageMath
    def A362991Triangle(size):  # 'size' is the number of rows.
        A, T, l = [], [], 1
        for n in range(size):
            A.append(Rational(1/(n + 1)))
            for j in range(n, 0, -1):
                A[j - 1] = j * (A[j - 1] - A[j])
            l = lcm(l, n + 1)
            T.append([a * l for a in A])
        return T
    A362991Triangle(10)

Formula

T(n, 0) = lcm(1, 2, ..., n+1) * Bernoulli(n, 1).
Showing 1-3 of 3 results.