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 1-9 of 9 results.

A223899 Poly-Cauchy numbers of the second kind hat c_n^(-2).

Original entry on oeis.org

1, -4, 13, -51, 244, -1392, 9260, -70508, 605320, -5788008, 61021872, -703384272, 8801449344, -118828732032, 1721888828928, -26656798602240, 439110126743040, -7669109089082880, 141557837068938240, -2753560001544053760, 56299265625742848000
Offset: 0

Views

Author

Takao Komatsu, Mar 29 2013

Keywords

Crossrefs

Programs

  • Magma
    [&+[StirlingFirst(n, k)*(-1)^k*(k+1)^2: k in [0..n]]: n in [0..23]]; // Vincenzo Librandi, Aug 03 2013
    
  • Mathematica
    Table[Sum[StirlingS1[n, k] (-1)^k (k + 1)^2, {k, 0, n}], {n, 0, 30}]
  • PARI
    a(n) = sum(k=0, n, stirling(n, k, 1)*(-1)^k*(k+1)^2); \\ Michel Marcus, Nov 14 2015

Formula

a(n) = Sum_{k=0..n} (-1)^k * (k+1)^2 * Stirling1(n,k).
E.g.f.: (1 - log(1 + x) * (3 - log(1 + x))) / (1 + x). - Ilya Gutkovskiy, Aug 09 2021
From Seiichi Manyama, Apr 15 2025: (Start)
E.g.f.: Sum_{k>=0} (k+1)^2 * (-log(1+x))^k / k!.
a(n) = (-1)^n * Sum_{k=0..2} k! * Stirling2(3,k+1) * |Stirling1(n+1,k+1)|. (End)

A222636 Poly-Cauchy numbers c_n^(-3).

Original entry on oeis.org

1, 8, 19, -1, -10, 48, -234, 1302, -8328, 60672, -497688, 4547448, -45846864, 505862064, -6065584128, 78555965184, -1093053332736, 16264215348480, -257730606190080, 4333624828853760, -77067187081620480, 1445257352902763520, -28505367984508416000
Offset: 0

Views

Author

Takao Komatsu, Mar 28 2013

Keywords

Comments

Definition of poly-Cauchy numbers in A222627.

Crossrefs

Column k=3 of A383049.
Cf. A223901.

Programs

  • Magma
    [&+[StirlingFirst(n,k)*(k+1)^3: k in [0..n]]: n in [0..25]]; // Bruno Berselli, Mar 28 2013
    
  • Mathematica
    Table[Sum[StirlingS1[n, k] (k + 1)^3, {k, 0, n}], {n, 0, 25}]
  • PARI
    a(n) = sum(k=0, n, stirling(n, k, 1)*(k+1)^3); \\ Michel Marcus, Nov 14 2015

Formula

a(n) = Sum_{k=0..n} Stirling1(n,k) * (k+1)^3.
E.g.f.: (1 + x) * (1 + 7 * log(1 + x) + 6 * log(1 + x)^2 + log(1 + x)^3). - Ilya Gutkovskiy, Aug 10 2021
E.g.f.: Sum_{k>=0} (k+1)^3 * log(1+x)^k / k!. - Seiichi Manyama, Apr 14 2025

A222748 Poly-Cauchy numbers c_n^(-4).

Original entry on oeis.org

1, 16, 65, 45, -116, 340, -1240, 5480, -28464, 169248, -1125840, 8197680, -63806016, 514314240, -4058967744, 26952984000, -37203513984, -4251686488704, 140692872720384, -3560137793538048, 84004474130786304, -1955196907518928896, 45927815909901004800
Offset: 0

Views

Author

Takao Komatsu, Mar 28 2013

Keywords

Comments

Definition of poly-Cauchy numbers in A222627.

Crossrefs

Column k=4 of A383049.

Programs

  • Magma
    [&+[StirlingFirst(n,k)*(k+1)^4: k in [0..n]]: n in [0..25]]; // Bruno Berselli, Mar 28 2013
    
  • Mathematica
    Table[Sum[StirlingS1[n, k] (k + 1)^4, {k, 0, n}], {n, 0, 25}]
  • PARI
    a(n) = sum(k=0, n, stirling(n, k, 1)*(k+1)^4); \\ Michel Marcus, Nov 14 2015

Formula

a(n) = Sum_{k=0..n} Stirling1(n,k) * (k+1)^4.
From Seiichi Manyama, Apr 14 2025: (Start)
E.g.f.: Sum_{k>=0} (k+1)^4 * log(1+x)^k / k!.
E.g.f.: (1+x) * Sum_{k=0..4} Stirling2(5,k+1) * log(1+x)^k. (End)

A223023 Poly-Cauchy numbers c_n^(-5).

Original entry on oeis.org

1, 32, 211, 359, -538, 984, -1866, 1110, 32640, -449760, 5035200, -55896960, 646005600, -7896549120, 102604234080, -1418189492640, 20828546505600, -324419255412480, 5346952977432960, -93035974518691200, 1705088403923592960, -32842738382065931520
Offset: 0

Views

Author

Takao Komatsu, Mar 28 2013

Keywords

Comments

Definition of poly-Cauchy numbers in A222627.

Crossrefs

Column k=5 of A383049.

Programs

  • Magma
    [&+[StirlingFirst(n,k)*(k+1)^5: k in [0..n]]: n in [0..25]]; // Bruno Berselli, Mar 28 2013
    
  • Mathematica
    Table[Sum[StirlingS1[n, k] (k + 1)^5, {k, 0, n}], {n, 0, 25}]
  • PARI
    a(n) = sum(k=0, n, stirling(n, k, 1)*(k+1)^5); \\ Michel Marcus, Nov 14 2015

Formula

a(n) = Sum_{k=0..n} Stirling1(n,k) * (k+1)^5.
From Seiichi Manyama, Apr 14 2025: (Start)
E.g.f.: Sum_{k>=0} (k+1)^5 * log(1+x)^k / k!.
E.g.f.: (1+x) * Sum_{k=0..5} Stirling2(6,k+1) * log(1+x)^k. (End)

A383049 Square array A(n,k), n >= 0, k >= 0, read by antidiagonals downwards, where A(n,k) is the n-th term of the inverse Stirling transform of j-> (j+1)^k.

Original entry on oeis.org

1, 1, 1, 1, 2, 0, 1, 4, 1, 0, 1, 8, 5, -1, 0, 1, 16, 19, -3, 2, 0, 1, 32, 65, -1, 4, -6, 0, 1, 64, 211, 45, -10, -8, 24, 0, 1, 128, 665, 359, -116, 48, 20, -120, 0, 1, 256, 2059, 2037, -538, 340, -234, -52, 720, 0, 1, 512, 6305, 10079, -1316, 984, -1240, 1302, 72, -5040, 0
Offset: 0

Views

Author

Seiichi Manyama, Apr 14 2025

Keywords

Examples

			Square array begins:
  1,  1,  1,    1,     1,     1,     1, ...
  1,  2,  4,    8,    16,    32,    64, ...
  0,  1,  5,   19,    65,   211,   665, ...
  0, -1, -3,   -1,    45,   359,  2037, ...
  0,  2,  4,  -10,  -116,  -538, -1316, ...
  0, -6, -8,   48,   340,   984, -1148, ...
  0, 24, 20, -234, -1240, -1866, 16400, ...
		

Crossrefs

Columns k=0..6 give A019590(n+1), A302190 (for n > 0), A222627, A222636, A222748, A223023, A383050.
Main diagonal gives A383051.

Programs

  • PARI
    a(n, k) = sum(j=0, n, (j+1)^k*stirling(n, j, 1));

Formula

A(n,k) = Sum_{j=0..n} (j+1)^k * Stirling1(n,j).
E.g.f. of column k: Sum_{j>=0} (j+1)^k * log(1+x)^j / j!.
E.g.f. of column k: (1+x) * Sum_{j=0..k} Stirling2(k+1,j+1) * log(1+x)^j.

A224094 Denominators of poly-Cauchy numbers c_n^(2).

Original entry on oeis.org

1, 4, 36, 48, 1800, 720, 35280, 20160, 226800, 10080, 731808, 665280, 1967565600, 11211200, 129729600, 34594560, 18745927200, 28641600, 371536925760, 3990729600, 3226504881600, 4877558400, 466663317120, 550720684800, 2192556726360000, 175404538108800
Offset: 0

Views

Author

Takao Komatsu, Mar 30 2013

Keywords

Comments

The poly-Cauchy numbers c_n^k can be expressed in terms of the (unsigned) Stirling numbers of the first kind: c_n^(k) = (-1)^n*sum(abs(stirling1(n,m))*(-1)^m/(m+1)^k, m=0..n).

Crossrefs

Cf. A006233, A222627, A224095 (numerators).

Programs

  • Mathematica
    Table[Denominator[Sum[StirlingS1[n, k]/ (k + 1)^2, {k, 0, n}]], {n, 0, 25}]
  • PARI
    a(n) = denominator(sum(k=0, n,stirling(n, k, 1)/(k+1)^2)); \\ Michel Marcus, Nov 15 2015

A224095 Numerators of poly-Cauchy numbers c_n^(2).

Original entry on oeis.org

1, 1, -5, 11, -1103, 1627, -374473, 1220651, -92146157, 31595747, -20000218625, 176776749931, -5607610511548471, 374753409522157, -55207553310144173, 202183428095237231, -1614396705602979083803
Offset: 0

Views

Author

Takao Komatsu, Mar 31 2013

Keywords

Comments

The poly-Cauchy numbers c_n^(k) can be expressed in terms of the (unsigned) Stirling numbers of the first kind: c_n^(k) = (-1)^n*sum(abs(stirling1(n,m))*(-1)^m/(m+1)^k, m=0..n).

Crossrefs

Cf. A006232, A222627, A224094 (denominators).

Programs

  • Mathematica
    Table[Numerator[Sum[StirlingS1[n, k]/ (k + 1)^2, {k, 0, n}]], {n, 0, 25}]
  • PARI
    a(n) = numerator(sum(k=0, n,stirling(n, k, 1)/(k+1)^2)); \\ Michel Marcus, Nov 15 2015

A223173 Poly-Cauchy numbers c_3^(-n).

Original entry on oeis.org

-1, -3, -1, 45, 359, 2037, 10079, 46365, 204119, 873477, 3666959, 15191085, 62342279, 254119317, 1030760639, 4165958205, 16792710839, 67557739557, 271392171119, 1089053371725, 4366669645799, 17498051254197, 70086331418399, 280627721655645
Offset: 1

Views

Author

Takao Komatsu, Mar 28 2013

Keywords

Comments

Definition of poly-Cauchy numbers in A222627.

Programs

  • Magma
    [&+[StirlingFirst(3,k)*(k+1)^n: k in [0..3]]: n in [1..25]]; // Bruno Berselli, Mar 28 2013
    
  • Maple
    seq(2^(n+1)-3^(n+1)+4^n, n=0..30); # Robert Israel, Jun 21 2018
  • Mathematica
    Table[Sum[StirlingS1[3, k] (k + 1)^n, {k, 0, 3}], {n, 25}]
  • PARI
    a(n) = sum(k=0, 3, stirling(3, k, 1)*(k+1)^n); \\ Michel Marcus, Nov 14 2015

Formula

a(n) = Sum_{k=0..3} Stirling1(3,k)*(k+1)^n.
From Colin Barker, Mar 31 2013: (Start)
Conjecture:
a(n) = 2^(1+n) - 3^(1+n) + 4^n;
g.f.: -x*(6*x-1) / ((2*x-1)*(3*x-1)*(4*x-1)). (End)
Conjecture verified by Robert Israel, Jun 21 2018

A223852 Poly-Cauchy numbers c_5^(-n).

Original entry on oeis.org

-6, -8, 48, 340, 984, -1148, -34152, -254780, -1250376, -3417788, 12508248, 296104900, 3122953464, 26485493572, 201873508248, 1443404093380, 9892106472504, 65798800964932, 428187502981848, 2740792716574660, 17321987718906744, 108394003491348292
Offset: 1

Views

Author

Takao Komatsu, Mar 28 2013

Keywords

Comments

Definition of poly-Cauchy numbers in A222627.

Programs

  • Magma
    [&+[StirlingFirst(5,k)*(k+1)^n: k in [0..5]]: n in [1..25]]; // Bruno Berselli, Mar 28 2013
    
  • Mathematica
    Table[Sum[StirlingS1[5, k] (k + 1)^n, {k, 0, 5}], {n, 25}]
  • PARI
    a(n) = sum(k=0, 5, stirling(5, k, 1)*(k+1)^n); \\ Michel Marcus, Nov 14 2015

Formula

a(n) = Sum_{k=0..5} Stirling1(5,k)*(k+1)^n.
Empirical g.f.: -2*x*(810*x^3 - 361*x^2 + 56*x - 3) / ((2*x-1)*(3*x-1)*(4*x-1)*(5*x-1)*(6*x-1)). - Colin Barker, Mar 31 2013
Showing 1-9 of 9 results.