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.

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A224374 T(n,k)=Number of nXk 0..2 arrays with rows unimodal and antidiagonals nondecreasing.

Original entry on oeis.org

3, 9, 9, 22, 54, 27, 46, 218, 324, 81, 86, 698, 1838, 1944, 243, 148, 1915, 7608, 15540, 11664, 729, 239, 4690, 26314, 77793, 132236, 69984, 2187, 367, 10511, 80819, 311367, 800309, 1126072, 419904, 6561, 541, 21919, 227112, 1092281, 3607078, 8297747
Offset: 1

Views

Author

R. H. Hardin Apr 05 2013

Keywords

Comments

Table starts
.....3........9.........22..........46...........86...........148
.....9.......54........218.........698.........1915..........4690
....27......324.......1838........7608........26314.........80819
....81.....1944......15540.......77793.......311367.......1092281
...243....11664.....132236......800309......3607078......13831334
...729....69984....1126072.....8297747.....42132769.....174854516
..2187...419904....9588028....86251004....495660330....2231009824
..6561..2519424...81634704...896856330...5848449149...28645726612
.19683.15116544..695055928..9325161494..69064897862..368818252942
.59049.90699264.5917866680.96954549463.815702088065.4752723627808

Examples

			Some solutions for n=3 k=4
..2..2..2..2....0..0..1..2....1..2..0..0....1..2..1..1....1..1..2..0
..2..2..2..1....2..2..2..2....2..1..1..1....2..2..2..2....1..2..2..0
..2..2..2..1....2..2..2..2....2..2..1..1....2..2..2..0....2..2..1..1
		

Crossrefs

Column 1 is A000244
Column 2 is 9*6^(n-1)
Row 1 is A223718
Row 2 is A223927

Formula

Empirical: columns k=1..7 have recurrences of order 1,1,5,7,11,14,19 for n>0,0,0,8,13,18,24
Empirical: rows n=1..7 are polynomials of order 4*n for k>0,0,0,2,3,4,5

A224190 T(n,k) = Number of n X k 0..2 arrays with rows unimodal and columns nondecreasing.

Original entry on oeis.org

3, 9, 6, 22, 36, 10, 46, 158, 100, 15, 86, 548, 684, 225, 21, 148, 1600, 3526, 2205, 441, 28, 239, 4102, 14751, 15779, 5852, 784, 36, 367, 9503, 52591, 89380, 55438, 13524, 1296, 45, 541, 20299, 165212, 422488, 408222, 163746, 28176, 2025, 55, 771, 40570
Offset: 1

Views

Author

R. H. Hardin Apr 01 2013

Keywords

Comments

Table starts
..3....9.....22......46.......86........148.........239..........367
..6...36....158.....548.....1600.......4102........9503........20299
.10..100....684....3526....14751......52591......165212.......468292
.15..225...2205...15779....89380.....422488.....1727738......6272940
.21..441...5852...55438...408222....2469182....12741432.....57644194
.28..784..13524..163746..1519738...11444292....72710554....400958714
.36.1296..28176..424326..4844576...44435746...340780382...2249643632
.45.2025..54153..992607.13669953..150015321..1366188661..10635858679
.55.3025..97570.2138488.34953776..452158538..4823267213..43724068755
.66.4356.166738.4305730.82399174.1240740774.15322738603.159999462711

Examples

			Some solutions for n=3, k=4
..1..2..2..1....0..0..2..0....1..2..1..1....0..1..0..0....1..0..0..0
..1..2..2..1....1..2..2..0....1..2..1..1....0..1..2..0....1..1..0..0
..2..2..2..2....1..2..2..1....2..2..1..1....0..2..2..0....1..1..0..0
		

Crossrefs

Column 1 is A000217(n+1).
Column 2 is A000537(n+1).
Row 1 is A223718.
Row 2 is A223919.
Row 3 is A223865.

Formula

Empirical: columns k=1..7 are polynomials of degree 2*k.
Empirical: rows n=1..7 are polynomials of degree 4*n.

A223933 T(n,k)=Number of nXk 0..2 arrays with rows, columns and antidiagonals unimodal and diagonals nondecreasing.

Original entry on oeis.org

3, 9, 9, 22, 54, 22, 46, 218, 218, 46, 86, 698, 1116, 698, 86, 148, 1915, 4498, 4498, 1915, 148, 239, 4690, 15791, 21334, 15791, 4690, 239, 367, 10511, 49646, 86439, 86439, 49646, 10511, 367, 541, 21919, 142177, 316136, 386495, 316136, 142177, 21919, 541
Offset: 1

Views

Author

R. H. Hardin Mar 29 2013

Keywords

Comments

Table starts
...3.....9......22.......46........86........148........239.........367
...9....54.....218......698......1915.......4690......10511.......21919
..22...218....1116.....4498.....15791......49646.....142177......375777
..46...698....4498....21334.....86439.....316136....1065625.....3337831
..86..1915...15791....86439....386495....1548633....5773556....20277077
.148..4690...49646...316136...1548633....6621074...26250443....98910688
.239.10511..142177..1065625...5773556...26250443..108796955...427868778
.367.21919..375777..3337831..20277077...98910688..427868778..1735753333
.541.43045..926559..9773219..67308910..356869229.1623374603..6788778441
.771.80334.2150622.26903878.211460339.1233491661.5968786086.25890527027

Examples

			Some solutions for n=3 k=4
..0..0..2..1....0..0..0..1....0..1..1..2....2..2..2..2....1..1..0..0
..0..1..1..2....0..2..1..1....0..0..2..2....1..2..2..2....1..1..1..2
..0..1..1..2....0..2..2..2....0..0..2..2....1..2..2..2....0..1..2..1
		

Crossrefs

Column 1 is A223718

Formula

Empirical: columns k=1..6 are polynomials of degree 4*k for n>0,0,3,6,9,12

A223742 T(n,k)=Number of nXk 0..2 arrays with rows, columns, diagonals and antidiagonals unimodal.

Original entry on oeis.org

3, 9, 9, 22, 81, 22, 46, 484, 484, 46, 86, 2116, 5600, 2116, 86, 148, 7396, 42090, 42090, 7396, 148, 239, 21904, 237088, 480236, 237088, 21904, 239, 367, 57121, 1082738, 3868968, 3868968, 1082738, 57121, 367, 541, 134689, 4207089, 24527068, 41586328
Offset: 1

Views

Author

R. H. Hardin Mar 26 2013

Keywords

Comments

Table starts
...3......9........22.........46...........86...........148............239
...9.....81.......484.......2116.........7396.........21904..........57121
..22....484......5600......42090.......237088.......1082738........4207089
..46...2116.....42090.....480236......3868968......24527068......129982953
..86...7396....237088....3868968.....41586328.....340038574.....2289596121
.148..21904...1082738...24527068....340038574....3437215802....28017383049
.239..57121...4207089..129982953...2289596121...28017383049...268717054875
.367.134689..14362171..597438379..13281578167..195114520747..2171612995939
.541.292681..44066468.2440360420..68222609208.1200776938428.15433289999394
.771.594441.123591226.9014646324.316008418514.6667000031694

Examples

			Some solutions for n=3 k=4
..0..1..1..2....1..2..1..0....1..1..1..0....0..0..0..0....0..0..1..2
..2..2..2..0....2..2..1..0....2..2..2..2....2..1..1..1....2..2..2..2
..1..2..0..0....0..0..2..0....0..2..1..1....1..2..0..0....0..2..2..1
		

Crossrefs

Column 1 is A223718
Column 2 is A223719

Formula

Empirical: columns k=1..6 are polynomials of degree 4*k for n>0,0,0,6,11,18

A223815 T(n,k)=Number of nXk 0..2 arrays with row sums nondecreasing and column sums unimodal.

Original entry on oeis.org

3, 9, 6, 22, 50, 10, 46, 337, 222, 15, 86, 1922, 4120, 867, 21, 148, 9783, 65465, 43941, 3123, 28, 239, 45537, 921010, 1941904, 426527, 10660, 36, 367, 198252, 11789302, 76453838, 52310070, 3875213, 35064, 45, 541, 817482, 139965348, 2740448352
Offset: 1

Views

Author

R. H. Hardin Mar 27 2013

Keywords

Comments

Table starts
..3.......9.........22...........46.............86.............148
..6......50........337.........1922...........9783...........45537
.10.....222.......4120........65465.........921010........11789302
.15.....867......43941......1941904.......76453838......2740448352
.21....3123.....426527.....52310070.....5767953144....581679349302
.28...10660....3875213...1313561156...405333095737.115166445136785
.36...35064...33540705..31302500115.26977674423993
.45..112373..279734339.716436867795
.55..353517.2266708593
.66.1097430

Examples

			Some solutions for n=3 k=4
..1..0..1..1....0..1..2..2....0..1..2..1....0..1..0..0....0..1..0..0
..1..2..1..0....1..2..2..0....2..2..0..0....0..2..1..0....0..1..1..0
..1..1..2..2....1..1..1..2....0..1..2..2....0..2..1..1....0..0..1..1
		

Crossrefs

Column 1 is A000217(n+1)
Column 2 is A222993
Row 1 is A223718

A223831 T(n,k)=Number of nXk 0..2 arrays with rows and columns unimodal.

Original entry on oeis.org

3, 9, 9, 22, 81, 22, 46, 484, 484, 46, 86, 2116, 6166, 2116, 86, 148, 7396, 51136, 51136, 7396, 148, 239, 21904, 310396, 738482, 310396, 21904, 239, 367, 57121, 1492552, 7291180, 7291180, 1492552, 57121, 367, 541, 134689, 5995781, 54035194, 111026387
Offset: 1

Views

Author

R. H. Hardin Mar 27 2013

Keywords

Comments

Table starts
...3......9........22..........46............86.............148
...9.....81.......484........2116..........7396...........21904
..22....484......6166.......51136........310396.........1492552
..46...2116.....51136......738482.......7291180........54035194
..86...7396....310396.....7291180.....111026387......1215505987
.148..21904...1492552....54035194....1215505987.....18986502099
.239..57121...5995781...320423509...10278415020....222531132820
.367.134689..20879061..1590193515...70637615542...2068398813560
.541.292681..64727664..6823643014..409495177832..15880238812350
.771.594441.182215264.25942390362.2059270878998.103853282918692

Examples

			Some solutions for n=3 k=4
..1..2..0..0....0..0..1..1....0..2..2..0....1..2..1..0....0..1..1..1
..2..2..0..0....1..2..1..1....0..2..2..2....0..2..1..1....1..1..2..2
..0..2..1..0....0..0..1..1....0..0..2..2....0..1..2..2....0..1..2..1
		

Crossrefs

Column 1 is A223718
Column 2 is A223719

Formula

Empirical: columns k=1..7 are polynomials of degree 4*k

A224057 T(n,k)=Number of nXk 0..2 arrays with rows and columns unimodal and antidiagonals nondecreasing.

Original entry on oeis.org

3, 9, 9, 22, 54, 22, 46, 218, 218, 46, 86, 698, 1232, 698, 86, 148, 1915, 5219, 5219, 1915, 148, 239, 4690, 18502, 27246, 18502, 4690, 239, 367, 10511, 57911, 115716, 115716, 57911, 10511, 367, 541, 21919, 164781, 428949, 568107, 428949, 164781, 21919, 541
Offset: 1

Views

Author

R. H. Hardin Mar 30 2013

Keywords

Comments

Table starts
...3.....9......22.......46........86........148.........239.........367
...9....54.....218......698......1915.......4690.......10511.......21919
..22...218....1232.....5219.....18502......57911......164781......433762
..46...698....5219....27246....115716.....428949.....1442005.....4492529
..86..1915...18502...115716....568107....2392915.....9064541....31777144
.148..4690...57911...428949...2392915...11231300....46853641...179545949
.239.10511..164781..1442005...9064541...46853641...212819499...880290006
.367.21919..433762..4492529..31777144..179545949...880290006..3903149379
.541.43045.1068664.13133871.104876598..646161612..3395883003.16032541293
.771.80334.2485274.36307595.329032264.2215310269.12434367863.62103561341

Examples

			Some solutions for n=3 k=4
..0..0..0..1....2..2..1..0....0..0..0..0....1..1..0..0....0..1..0..0
..1..1..1..0....2..2..1..0....2..0..0..0....1..2..0..0....1..2..0..0
..1..2..1..0....2..2..0..0....2..1..1..1....2..2..2..1....2..2..0..0
		

Crossrefs

Column 1 is A223718
Column 2 is A223927

Formula

Empirical: columns k=1..7 are polynomials of degree 4*k for n>0,0,1,3,5,7,9

A223885 T(n,k)=Number of nXk 0..2 arrays with row sums unimodal and column sums inverted unimodal.

Original entry on oeis.org

3, 9, 9, 22, 81, 22, 46, 564, 564, 46, 86, 3298, 11250, 3298, 86, 148, 17048, 187019, 187019, 17048, 148, 239, 80412, 2718572, 8872648, 2718572, 80412, 239, 367, 353485, 35673854, 367614623, 367614623, 35673854, 353485, 367, 541, 1469903, 431939504
Offset: 1

Views

Author

R. H. Hardin Mar 28 2013

Keywords

Comments

Table starts
...3.......9.........22...........46............86...........148
...9......81........564.........3298.........17048.........80412
..22.....564......11250.......187019.......2718572......35673854
..46....3298.....187019......8872648.....367614623...13705619321
..86...17048....2718572....367614623...43524907508.4637374623582
.148...80412...35673854..13705619321.4637374623582
.239..353485..431939504.469700382368
.367.1469903.4901224903
.541.5845411
.771

Examples

			Some solutions for n=3 k=4
..1..0..1..2....0..1..0..2....1..1..0..1....1..1..0..0....1..0..2..1
..2..1..1..1....2..2..1..1....1..1..1..0....2..2..1..1....0..2..1..1
..2..0..0..2....2..0..2..1....0..0..1..0....1..1..2..2....2..2..1..2
		

Crossrefs

Column 1 is A223718

A279006 Alternating Jacobsthal triangle read by rows (second version).

Original entry on oeis.org

1, 1, 1, 1, 0, 1, 1, -1, 1, 1, 1, -2, 2, 0, 1, 1, -3, 4, -2, 1, 1, 1, -4, 7, -6, 3, 0, 1, 1, -5, 11, -13, 9, -3, 1, 1, 1, -6, 16, -24, 22, -12, 4, 0, 1, 1, -7, 22, -40, 46, -34, 16, -4, 1, 1, 1, -8, 29, -62, 86, -80, 50, -20, 5, 0, 1, 1, -9, 37, -91, 148, -166, 130, -70, 25, -5, 1, 1
Offset: 0

Views

Author

N. J. A. Sloane, Dec 07 2016

Keywords

Examples

			Triangle begins:
  1,
  1,   1,
  1,   0,   1,
  1,  -1,   1,   1,
  1,  -2,   2,   0,   1,
  1,  -3,   4,  -2,   1,   1,
  1,  -4,   7,  -6,   3,   0,   1,
  1,  -5,  11, -13,   9,  -3,   1,   1,
  1,  -6,  16, -24,  22, -12,   4,   0,   1,
  ...
		

Crossrefs

See A112468, A112555 and A108561 for other versions.

Programs

  • Maple
    T := (n, k) -> local j; add((-1)^j*binomial(n-k-1+j, j), j = 0..k):
    seq(print(seq(T(n, k), k = 0..n)), n = 0..9);  # Peter Luschny, Aug 30 2024
  • Mathematica
    T[i_, i_] = T[, 0] = 1; T[i, j_] := T[i, j] = T[i-1, j] - T[i-1, j-1];
    Table[T[i, j], {i, 0, 11}, {j, 0, i}] // Flatten (* Jean-François Alcover, Sep 06 2018 *)
    T[n_, k_] := 2^k*Hypergeometric2F1[-n, -k, -k, 1/2]; Table[T[n, k], {n, 0, 11}, {k, 0, n}]//Flatten (* Detlef Meya, Aug 30 2024 *)
  • PARI
    \\ using arxiv (3.1) and (3.7) formulas where A is A220074 and B is this sequence
    A(i, j) = if ((i < 0), 0, if (j==0, 1, A(i - 1, j - 1) - A(i - 1, j))); \\ A220074
    B(i, j) = A(i, i-j);
    tabl(nn) = for (i=0, nn, for (j=0, i, print1(B(i,j), ", ")); print()); \\ Michel Marcus, Jun 17 2017

Formula

T(i, j) = A220074(i, i-j). See (3.7) in arxiv link. - Michel Marcus, Jun 17 2017
T(n, k) = 2^k*hypergeom([-n, -k], [-k], 1/2). - Detlef Meya, Aug 30 2024

Extensions

More terms from Michel Marcus, Jun 17 2017

A220074 Triangle read by rows giving coefficients T(n,k) of [x^(n-k)] in Sum_{i=0..n} (x-1)^i, 0 <= n <= k.

Original entry on oeis.org

1, 1, 0, 1, -1, 1, 1, -2, 2, 0, 1, -3, 4, -2, 1, 1, -4, 7, -6, 3, 0, 1, -5, 11, -13, 9, -3, 1, 1, -6, 16, -24, 22, -12, 4, 0, 1, -7, 22, -40, 46, -34, 16, -4, 1, 1, -8, 29, -62, 86, -80, 50, -20, 5, 0, 1, -9, 37, -91, 148, -166, 130, -70, 25, -5, 1
Offset: 0

Views

Author

Mokhtar Mohamed, Dec 03 2012

Keywords

Comments

If the triangle is viewed as a square array S(m, k) = T(m+k, k), 0 <= m, 0 <= k, its first row is (1,0,1,0,1,...) with e.g.f. cosh(x), g.f. 1/(1-x^2) and subsequent rows have g.f. 1/((1+x)^n*(1-x^2)) (substitute x for -x in g.f. for A059259).
By column, S(m, k) is the coefficient of [x^m] in the generating function Sum_{i=0..k} (-1)^i/(1-x)^(i+1).
This is a rational generating function down column k with a power of (1-x) in the denominator; therefore column k is a polynomial in m respectively n. - Mathew Englander, May 14 2014
Column k multiplied by k! seems to correspond to row k of A054651, considered as a polynomial and then evaluated on the negative integers. For example, row 5 of A054651 represents the polynomial x^5 - 5*x^4 + 25*x^3 + 5*x^2 + 94*x + 120. Evaluating that for x = -1, x = -2, x = -3, ... gives (0, -360, -1440, -4080, -9600, -19920, -37680, ...) which is 5! times column 5 of this triangle. - Mathew Englander, May 23 2014
This triangle provides a solution to a question in the mathematics of gambling. For 0 < p < 1 and positive integers N and G with N < G, suppose you begin with N dollars and make repeated wagers, each time winning 1 dollar with probability p and losing 1 dollar with probability 1-p. You continue betting 1 dollar at a time until you have either G dollars (your Goal) or 0 (bankrupt). What is the probability of reaching your Goal before going bankrupt, as a function of p, N, and G? (This is a type of one-dimensional random walk.) Answer: Let Q_m_(x) be the polynomial whose coefficients are given by row m-1 of the triangle (e.g., Q_6_(x) = 1 - 4x + 7x^2 - 6x^3 + 3x^4). Then, the probability of reaching G dollars before going bankrupt is p^(G-N)*Q_N_(p)/Q_G_(p). - Mathew Englander, May 23 2014
From Paul Curtz, Mar 17 2017: (Start)
Consider the triangle Ja(n+1,k) (here, but generally Ja(n,k)) composed of the triangle a(n) prepended with a column of 0's, i.e.,
0;
0, 1;
0, 1, 0;
0, 1, -1, 1;
0, 1, -2, 2, 0;
0, 1, -3, 4, -2, 1;
0, 1, -4, 7, -6, 3, 0;
0, 1, -5, 11, -13, 9, -3, 1;
... .
The row sums are 0, 1, 1, ... = A057427(n), the most elementary autosequence of the first kind (a sequence of the first kind has 0's as main diagonal of its array of successive differences).
The row sums of the absolute values are A001045(n).
Ja applied to a sequence written in its reluctant form yields an autosequence of the first kind. Example: the reluctant form of A001045(n) is 0, 0, 1, 0, 1, 1, 0, 1, 1, 3, 0, 1, 1, 3, 5, ... = Jl.
Jl multiplied by Ja gives the triangle Jal:
0;
0, 1;
0, 1, 0;
0, 1, -1, 3;
0, 1, -2, 6, 0;
0, 1, -3, 12, -10, 11;
0, 1, -4, 21, -30, 33, 0;
0, 1, -5, 33, -65, 99, -63, 43;
... .
The row sums are A001045(n). (End)

Examples

			Triangle begins:
  1;
  1,   0;
  1,  -1,   1;
  1,  -2,   2,    0;
  1,  -3,   4,   -2,    1;
  1,  -4,   7,   -6,    3,    0;
  1,  -5,  11,  -13,    9,   -3,    1;
  1,  -6,  16,  -24,   22,  -12,    4,    0;
  1,  -7,  22,  -40,   46,  -34,   16,   -4,   1;
  1,  -8,  29,  -62,   86,  -80,   50,  -20,   5,   0;
  1,  -9,  37,  -91,  148, -166,  130,  -70,  25,  -5, 1;
  1, -10,  46, -128,  239, -314,  296, -200,  95, -30, 6, 0;
  ...
		

Crossrefs

Similar to the triangles A080242, A108561, A112555, A071920.
Cf. A000124 (column 2), A003600 (column 3), A223718 (column 4, conjectured), A257890 (column 5).

Programs

  • GAP
    Flat(List([0..12], n-> List([0..n], k-> Sum([0..k], j-> (-1)^j*Binomial(n-k+j, j))))); # G. C. Greubel, Feb 18 2019
  • Magma
    [[(&+[(-1)^j*Binomial(n-k+j, j): j in [0..k]]): k in [0..n]]: n in [0..12]]; // G. C. Greubel, Feb 18 2019
    
  • Maple
    A059259A := proc(n,k)
        1/(1+y)/(1-x-y) ;
        coeftayl(%,x=0,n) ;
        coeftayl(%,y=0,k) ;
    end proc:
    A059259 := proc(n,k)
        A059259A(n-k,k) ;
    end proc:
    A220074 := proc(i,j)
        (-1)^j*A059259(i,j) ;
    end proc: # R. J. Mathar, May 14 2014
  • Mathematica
    Table[Sum[(-1)^i*Binomial[n-k+i,i], {i, 0, k}], {n, 0, 12}, {k, 0, n} ]//Flatten (* Michael De Vlieger, Jan 27 2016 *)
  • PARI
    {T(n,k) = sum(j=0,k, (-1)^j*binomial(n-k+j,j))};
    for(n=0,12, for(k=0,n, print1(T(n,k), ", "))) \\ G. C. Greubel, Feb 18 2019
    
  • Sage
    [[sum((-1)^j*binomial(n-k+j,j) for j in (0..k)) for k in (0..n)] for n in (0..12)] # G. C. Greubel, Feb 18 2019
    

Formula

Sum_{k=0..n} T(n,k) = 1.
T(n,k) = Sum_{i=0..k} (-1)^i*binomial(n-k+i, i).
T(2*n,n) = (-1)^n*A026641(n).
T(n,k) = (-1)^k*A059259(n,k).
T(n,0) = 1, T(n,n) = (1+(-1)^n)/2, and T(n,k) = T(n-1,k) - T(n-1,k-1) for 0 < k < n. - Mathew Englander, May 24 2014

Extensions

Definition and comments clarified by Li-yao Xia, May 15 2014
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