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.

User: Igor Victorovich Statsenko

Igor Victorovich Statsenko's wiki page.

Igor Victorovich Statsenko has authored 13 sequences. Here are the ten most recent ones:

A381082 Triangle T(n,k) read by rows, where the columns are the coefficients of the standard expansion of the function f(x) = (-log(1-x))^(k)*exp(-m*x)/k! for the case m=2.

Original entry on oeis.org

1, -2, 1, 4, -3, 1, -8, 8, -3, 1, 16, -18, 11, -2, 1, -32, 44, -20, 15, 0, 1, 64, -80, 94, 5, 25, 3, 1, -128, 272, 56, 294, 105, 49, 7, 1, 256, 112, 1868, 1596, 1169, 392, 98, 12, 1, -512, 5280, 12216, 16148, 10290, 4305, 1092, 186, 18, 1
Offset: 0

Author

Keywords

Examples

			Triangle starts:
  [0]     1;
  [1]    -2,      1;
  [2]     4,     -3,       1;
  [3]    -8,      8,      -3,       1;
  [4]    16,    -18,      11,      -2,       1;
  [5]   -32,     44,     -20,      15,       0,        1;
  [6]    64,    -80,      94,       5,      25,        3,     1;
  [7]  -128,    272,      56,     294,     105,       49,     7,     1;
  [8]   256,    112,    1868,    1596,    1169,      392,    98,    12,    1;
  [9]  -512,   5280,   12216,   16148,   10290,     4305,  1092,   186,   18,     1;
  ...
		

Crossrefs

Cf. A000023 (row sums).
Columns 0,1: A122803, A346397.
Triangles: for m = -3 is A327997; for m = -2 is A137346 (unsigned); for m = -1 is A094816; for m = 0 is A132393; for m = 1 is A269953.

Programs

  • Maple
    T:=(m,n,k)->add(Stirling1(n-i,k)*binomial(n,i)*m^(i)*(-1)^(n-k), i=0..n):
    m:=2:seq(print(seq(T(m,n,k), k=0..n)), n=0..9);

Formula

T(n,k) = Sum_{i=0..n} Stirling1(n-i, k)*binomial(n, i)*m^(i)*(-1)^(n-k), where m = 2.

A380851 Riordan array ((1-x)^(m-1), x/(1-x)) with factor r^(2*n) on row n, for m = 3/2, r = 2.

Original entry on oeis.org

1, -2, 4, -2, 8, 16, -4, 24, 96, 64, -10, 80, 480, 640, 256, -28, 280, 2240, 4480, 3584, 1024, -84, 1008, 10080, 26880, 32256, 18432, 4096, -264, 3696, 44352, 147840, 236544, 202752, 90112, 16384, -858, 13728, 192192, 768768, 1537536, 1757184, 1171456, 425984, 65536
Offset: 0

Author

Keywords

Examples

			Triangle starts:
       k = 0      1       2        3        4        5       6
  n=0:     1;
  n=1:    -2,     4;
  n=2:    -2,     8,     16;
  n=3:    -4,    24,     96,      64;
  n=4:   -10,    80,    480,     640,     256;
  n=5:   -28,   280,   2240,    4480,    3584,    1024;
  n=6:   -84,  1008,  10080,   26880,   32256,   18432,   4096;
		

Crossrefs

Columns: A002420 (k=0); A240530 (k=1).
Triangle for m=-3, r=1: A104713; for m=-2, r=1: A104712; for m=-1, r=1: A135278; for m=0, r=1: A007318; for m=1, r=1: A097805; for m=2, r=1: A159854.

Programs

  • Maple
    T:=(m,r,n,k)->add(binomial(i+m,m)*binomial(n+1,n-k-i)*r^(2*n)*(-1)^(i),i=0..n-k): m:=3/2: r:=2: seq(print(seq(T(m,r,n,k), k=0..n)), n=0..10);
  • Mathematica
    T[n_, k_] := 4^n Binomial[n, k] Hypergeometric2F1[3/2, k - n, k + 1, 1];
    Table[T[n, k], {n, 0, 8}, {k, 0, n}] // Flatten  (* Peter Luschny, Feb 07 2025 *)
  • SageMath
    # Using function riordan_array from A256893.
    RA = riordan_array((1 - x)^(3/2 - 1), x/(1-x), 7)
    for n in range(7): print(4^n * RA.row(n)[:n+1])  # Peter Luschny, Feb 28 2025

Formula

T(n,k) = Sum_{i=0..n-k} binomial(i+m, m)*binomial(n+1, n-k-i)*r^(2*n)*(-1)^(i), for m = 3/2 and r = 2.
From Peter Luschny, Feb 07 2025: (Start)
T(n,k) = r^(2*n)*JacobiP(n - k, 1 + k, m - 1 - n, -1).
T(n,k) = 4^n*binomial(n, k)*hypergeom([3/2, k - n], [k + 1], 1). (End)

A377058 Triangle of generalized Stirling numbers of the lower level of the hierarchy (case m=2).

Original entry on oeis.org

1, 5, 1, 32, 11, 1, 248, 113, 18, 1, 2248, 1230, 263, 26, 1, 23272, 14534, 3765, 505, 35, 1, 270400, 186992, 55654, 9115, 865, 45, 1, 3479744, 2612000, 865186, 163779, 19110, 1372, 56, 1, 49079936, 39434448, 14235388, 3013164, 408569, 36288, 2058, 68, 1
Offset: 0

Author

Keywords

Comments

These numbers are a subset of the generalized Stirling numbers introduced in A370518. Therefore, we assume them to be numbers of the lower level of hierarchy with respect to A370518.

Examples

			[0]           1;
[1]           5,          1;
[2]          32,         11,         1;
[3]         248,        113,        18,        1;
[4]        2248,       1230,       263,       26,       1;
[5]       23272,      14534,      3765,      505,      35,      1;
[6]      270400,     186992,     55654,     9115,     865,     45,     1;
[7]     3479744,    2612000,    865186,   163779,   19110,   1372,    56,    1;
[8]    49079936,   39434448,  14235388,  3013164,  408569,  36288,  2058,   68,    1;
		

Crossrefs

A361649 (row sums).
Triangle for m=0: A130534.
Triangle for m=1: A376863.

Programs

  • Maple
    T := (m,n,k) -> add(add(Stirling1(n-j,k)*binomial(n+m,i)*binomial(n,j)*binomial(j,i)*i!*m^(j-i), j=i..n), i=0..n): m:=2: seq(seq(T(m,n,k), k=0..n), n=0..10);

Formula

T(m, n, k) = Sum_{i=0..n} Sum_{j=i..n} Stirling1(n-j, k)*binomial(n+m, i)*binomial(n, j)* binomial(j, i)*i!*m^(j-i), for m = 2.

A376634 Triangle read by rows: T(n, k) = Sum_{i=0..n-k} Stirling1(i + m, m)*binomial(n+m+1, n-k-i)*(n + m - k)!/(i + m)!, for m = 2.

Original entry on oeis.org

1, 9, 1, 71, 12, 1, 580, 119, 15, 1, 5104, 1175, 179, 18, 1, 48860, 12154, 2070, 251, 21, 1, 509004, 133938, 24574, 3325, 335, 24, 1, 5753736, 1580508, 305956, 44524, 5000, 431, 27, 1, 70290936, 19978308, 4028156, 617624, 74524, 7155, 539, 30, 1, 924118272, 270074016, 56231712, 8969148, 1139292, 117454, 9850, 659, 33, 1, 13020978816, 3894932448, 832391136, 136954044, 18083484, 1961470, 176554, 13145, 791, 36, 1
Offset: 0

Author

Keywords

Comments

The columns of the triangle T(m,n,k) represent the coefficients of the asymptotic expansion of the higher order exponential integral E(x,m+1,k+2), for m=2, k>=0. For reference see. A163931.

Examples

			Triangle starts:
 [0]          1;
 [1]          9,          1;
 [2]         71,         12,          1;
 [3]        580,        119,         15,        1;
 [4]       5104,       1175,        179,       18,        1;
 [5]      48860,      12154,       2070,      251,       21,       1;
 [6]     509004,     133938,      24574,     3325,      335,      24,     1;
 [7]    5753736,    1580508,     305956,    44524,     5000,     431,    27,     1;
		

Crossrefs

Column k: A001706 (k=0), A001712 (k=1), A001717 (k=2), A001722 (k=3), A051525 (k=4), A051546 (k=5), A051561 (k=6).
Cf. A094587 and A173333 for m=0, A376582 for m=1.

Programs

  • Maple
    T:=(m,n,k)->add(Stirling1(i+m,m)*binomial(n+m+1,n-k-i)*(n+m-k)!/(i+m)!,i=0..n-k):m:=2:seq(seq(T(m,n,k), k=0..n),n=0..10);

A376863 Triangle of generalized Stirling numbers of the lower level of the hierarchy (section m=1).

Original entry on oeis.org

1, 3, 1, 13, 7, 1, 73, 50, 12, 1, 501, 400, 125, 18, 1, 4051, 3609, 1335, 255, 25, 1, 37633, 36463, 15214, 3485, 460, 33, 1, 394353, 408694, 186949, 48769, 7805, 763, 42, 1, 4596553, 5036792, 2479602, 714364, 131299, 15708, 1190, 52, 1, 58941091, 67714809, 35419350, 11045558, 2256933, 312375, 29190, 1770, 63, 1, 824073141, 986271823, 543025851, 180766890, 40194965, 6221397, 676893, 50970, 2535, 75, 1
Offset: 0

Author

Keywords

Examples

			Triangle starts:
[0]        1;
[1]        3,        1;
[2]       13,        7,        1;
[3]       73,       50,       12,       1;
[4]      501,      400,      125,      18,       1;
[5]     4051,     3609,     1335,     255,      25,       1;
[6]    37633,    36463,    15214,    3485,     460,      33,      1;
[7]   394353,   408694,   186949,   48769,    7805,     763,     42,    1;
[8]  4596553,  5036792,  2479602,  714364,  131299,   15708,   1190,   52,     1;
		

Crossrefs

A000262 (column 0), A052852 (row sums).
Triangle for m=0: A130534.

Programs

  • Maple
    T:=(m,n,k)->add(add(Stirling1(n-j,k)*binomial(n+m,i)*binomial(n,j)*binomial(j,i)*i!*m^(j-i), j=i..n),i=0..n):m:=1:seq(seq(T(m,n,k),k=0..n),n=0..10);

Formula

T(m, n, k) = Sum_{i=0..n} Sum_{j=i..n} Stirling1(n-j, k) * binomial(n+m, i) * binomial(n, j)* binomial(j, i) * i! * m^(j - i), for m = 1.

A376582 Triangle of generalized Stirling numbers.

Original entry on oeis.org

1, 5, 1, 26, 7, 1, 154, 47, 9, 1, 1044, 342, 74, 11, 1, 8028, 2754, 638, 107, 13, 1, 69264, 24552, 5944, 1066, 146, 15, 1, 663696, 241128, 60216, 11274, 1650, 191, 17, 1, 6999840, 2592720, 662640, 127860, 19524, 2414, 242, 19, 1, 80627040, 30334320, 7893840, 1557660, 245004, 31594, 3382, 299, 21, 1
Offset: 0

Author

Keywords

Examples

			Triangle starts:
[0]       1;
[1]       5,       1;
[2]      26,       7,       1;
[3]     154,      47,       9,        1;
[4]    1044,     342,      74,       11,       1;
[5]    8028,    2754,     638,      107,      13,     1;
[6]   69264,   24552,    5944,     1066,     146,    15,    1;
[7]  663696,  241128,   60216,    11274,    1650,   191,   17,    1;
		

Crossrefs

Column k: A001705 (k=0), A001711 (k=1), A001716 (k=2), A001721 (k=3), A051524 (k=4), A051545 (k=5), A051560 (k=6).
Cf. A094587 and A173333 for m=0.

Programs

  • Maple
    T:=(m,n,k)->add(Stirling1(i+m,m)*binomial(n+m+1,n-k-i)*(n+m-k)!/(i+m)!,i=0..n-k): m:=1: seq(seq(T(m,n,k), k=0..n), n=0..10);

Formula

T(m,n,k) = Sum_{i=0..n-k} Stirling1(i+m,m)*binomial(n+m+1,n-k-i)*(n+m-k)!/(i+m)!, for m=1.

A370518 Triangle of numbers read by rows: T(n,k) = Sum_{i=0..n} binomial(n,i)*(n-i)!*Stirling1(i,k)*TC(n,i) where TC(n,k) = Sum_{i=0..n-k} binomial(n+1,n-k-i)*Stirling2(i+3,i+1)*(-1)^(i) for n >= 0, 0 <= k <= n.

Original entry on oeis.org

1, -5, 1, 14, -9, 1, -18, 29, -12, 1, 0, -22, 35, -14, 1, 0, -26, 15, 25, -15, 1, 0, -60, 4, 75, -5, -15, 1, 0, -204, -56, 259, 70, -56, -14, 1, 0, -912, -484, 1092, 609, -168, -126, -12, 1, 0, -5040, -3708, 5480, 4599, -231, -882, -210, -9, 1, 0, -33120, -30024, 31820, 36350, 3675, -6027, -2370, -300, -5, 1
Offset: 0

Author

Keywords

Comments

Generalized Stirling numbers of the first kind of the second order.

Examples

			n\k     0     1     2     3     4     5     6
0:      1
1:     -5     1
2:     14    -9     1
3:    -18    29   -12     1
4:      0   -22    35   -14     1
5:      0   -26    15    25   -15     1
6:      0   -60     4    75    -5   -15     1
		

Crossrefs

For m=0 the formula gives the sequence A130534; for m=1 the formula gives the sequence A094645. In this case, we assume that A130534 consists of generalized Stirling numbers of the first kind of zero order, and A094645 consists of generalized Stirling numbers of the first kind of the first order.

Programs

  • Maple
    C:=(n,k)->n!/(k!*(n-k)!) : T0:=(m,n,k)->sum(C(n+1,n-k-p)*Stirling2(p+m+1,p+1)*((-1)^p), p=0..n-k) : T:=(m,n,k)->sum(C(n,r)*(n-r)!*Stirling1(r,k)*T0(m,n,r), r=0..n)  m:=2 : seq(seq T(m,n,k), k=0..n), n=0..10);

Formula

T(n,k) = Sum_{i=0..n} binomial(n,i)*(n-i)!*Stirling1(i,k)*TC(m,n,i) where TC(m,n,k) = Sum_{i=0..n-k} binomial(n+1,n-k-i)*Stirling2(i+m+1,i+1)*(-1)^(i),m = 2 for n >= 0.

A370516 Triangle of numbers read by rows: T(n,k) = Sum_{i=0..n-k} binomial(n+1,n-k-i)*Stirling2(i+3,i+1)*(-1)^i for n >= 0, 0 <= k <= n.

Original entry on oeis.org

1, -5, 1, 7, -4, 1, -3, 3, -3, 1, 0, 0, 0, -2, 1, 0, 0, 0, -2, -1, 1, 0, 0, 0, -2, -3, 0, 1, 0, 0, 0, -2, -5, -3, 1, 1, 0, 0, 0, -2, -7, -8, -2, 2, 1, 0, 0, 0, -2, -9, -15, -10, 0, 3, 1, 0, 0, 0, -2, -11, -24, -25, -10, 3, 4
Offset: 0

Author

Keywords

Comments

Generalized binomial coefficients of the second order.

Examples

			n\k   0    1    2    3    4    5    6
0:    1
1:   -5    1
2:    7   -4    1
3:   -3    3   -3    1
4:    0    0    0   -2    1
5:    0    0    0   -2   -1    1
6:    0    0    0   -2   -3    0    1
		

Crossrefs

For m=0 the formula gives the sequence A007318; for m=1 the formula gives the sequence A159854. In this case, we assume that A007318 consists of generalized binomial coefficients of order zero and A159854 consists of generalized binomial coefficients of order one.

Programs

  • Maple
    C:=(n,k)->n!/(k!*(n-k)!) : T:=(m,n,k)->sum(C(n+1,n-k-r)*Stirling2(r+m+1,r+1)*((-1)^r), r=0..n-k) : m:=2 : seq(seq T(m,n,k), k=0..n), n=0..10);

Formula

T(n,k) = Sum_{i=0..n-k} binomial(n+1,n-k-i)*Stirling2(i+m+1,i+1)*(-1)^i where m = 2 for n >= 0, 0 <= k <= n.

A369381 Triangle of numbers read by rows T(n,k) = binomial(n+1,k+1)*Stirling2(n+k,k).

Original entry on oeis.org

1, 0, 1, 0, 3, 7, 0, 6, 60, 90, 0, 10, 310, 1505, 1701, 0, 15, 1260, 14490, 46620, 42525, 0, 21, 4445, 105875, 716205, 1727110, 1323652, 0, 28, 14280, 653100, 8162000, 38623200
Offset: 0

Author

Keywords

Comments

The triangle T(n,k) is a functional dual of the triangle A269939 in identity: B(n) = Sum_{k=0..n}(-1)^(k)*A269939(n,k)/Binomial(n+k,k) = Sum_{k=0..n}(-1)^(k)*T(n,k)/Binomial(n+k,k). Where B(n) are the Bernoulli numbers.

Examples

			n\k  0      1       2        3        4       5
0:    1
1:    0      1
2:    0      3       7
3:    0      6      60       90
4:    0     10     310     1505     1701
5:    0     15    1260    14490    46620    42525
		

Crossrefs

Cf. A007820 (right diagonal).

Programs

  • Maple
    T:=(n,k)->((n+1)!/((k+1)!*(n-k)!))*Stirling2(n+k,k):seq(seq T(n,k),k=0..n), n=0..10);

Formula

T(n,k) = binomial(n+1,k+1)*Stirling2(n+k,k).

A362791 Triangle of numbers read by rows, T(n, k) = (n*(n-1)*(n-2))*Stirling2(k, 3), for n >= 1 and 1 <= k <= n.

Original entry on oeis.org

0, 0, 0, 0, 0, 6, 0, 0, 24, 144, 0, 0, 60, 360, 1500, 0, 0, 120, 720, 3000, 10800, 0, 0, 210, 1260, 5250, 18900, 63210, 0, 0, 336, 2016, 8400, 30240, 101136, 324576, 0, 0, 504, 3024, 12600, 45360, 151704, 486864, 1524600, 0, 0, 720, 4320, 18000, 64800, 216720, 695520, 2178000, 6717600
Offset: 1

Author

Keywords

Comments

T(n, k) is the number of ways to distribute k labeled items into n labeled boxes so that there are exactly 3 nonempty boxes.

Examples

			n\k   1      2      3      4      5      6      7
1:    0
2:    0      0
3:    0      0      6
4:    0      0     24    144
5:    0      0     60    360   1500
6:    0      0    120    720   3000  10800
7:    0      0    210   1260   5250  18900  63210
  ...
T(4,3) = 24:  {1}{2}{3}{} (24 ways).
T(4,4) = 144: {12}{3}{4}{} (144 ways).
		

Crossrefs

Cf. A002024 (case L=1), A362685 (case L=2), A068605 (right diagonal).

Programs

  • Maple
    L := 3: T := (n, k) -> pochhammer(-n, L)*Stirling2(k, L)*((-1)^L):
    seq(seq(T(n, k), k = 1..n), n = 1..10);
  • Python
    from math import isqrt, comb
    from sympy.functions.combinatorial.numbers import stirling
    def A362791(n): return (a:=(m:=isqrt(k:=n<<1))+(k>m*(m+1)))*(a-1)*(a-2)*stirling(n-comb(a,2),3) # Chai Wah Wu, Jun 20 2025

Formula

T(n, k) = (n!/(n - L)!) * Stirling2(k, L) with L = 3, T(1,1)=T(2,1)=T(2,2) = 0.