A114164
Riordan array (1/(1-2x), x(1-x)/(1-2x)^2).
Original entry on oeis.org
1, 2, 1, 4, 5, 1, 8, 18, 8, 1, 16, 56, 41, 11, 1, 32, 160, 170, 73, 14, 1, 64, 432, 620, 377, 114, 17, 1, 128, 1120, 2072, 1666, 704, 164, 20, 1, 256, 2816, 6496, 6608, 3649, 1178, 223, 23, 1, 512, 6912, 19392, 24192, 16722, 7001, 1826, 291, 26, 1, 1024, 16640, 55680, 83232, 69876, 36365, 12235, 2675, 368, 29, 1
Offset: 0
Triangle begins:
1;
2, 1;
4, 5, 1;
8, 18, 8, 1;
16, 56, 41, 11, 1;
32, 160, 170, 73, 14, 1;
...
A123878
Product of signed and unsigned Morgan-Voyce triangles.
Original entry on oeis.org
1, 0, 1, -1, 0, 1, -1, -3, 0, 1, 0, -3, -5, 0, 1, 1, 3, -5, -7, 0, 1, 1, 9, 10, -7, -9, 0, 1, 0, 5, 25, 21, -9, -11, 0, 1, -1, -9, 5, 49, 36, -11, -13, 0, 1, -1, -18, -50, -7, 81, 55, -13, -15, 0, 1, 0, -7, -70, -147, -39, 121, 78, -15, -17, 0, 1
Offset: 0
Number triangle begins:
1;
0, 1;
-1, 0, 1;
-1, -3, 0, 1;
0, -3, -5, 0, 1;
1, 3, -5, -7, 0, 1;
1, 9, 10, -7, -9, 0, 1;
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B:=Binomial;; Flat(List([0..12], n-> List([0..n], k-> Sum([0..n], j-> (-1)^(j-k)*B(n+j,2*j)*B(n+j,2*k) )))); # G. C. Greubel, Aug 08 2019
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B:= Binomial; [(&+[(-1)^(j-k)*B(n+j,2*j)*B(n+j,2*k):j in [0..n]]) : k in [0..n], n in [0..12]]; // G. C. Greubel, Aug 08 2019
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Table[Sum[(-1)^(j-k)*Binomial[n+j,2*j]*Binomial[j+k,2*k], {j,0,n}], {n, 0, 12}, {k,0,n}]//Flatten (* G. C. Greubel, Aug 08 2019 *)
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T(n,k) = sum(j=0,n, (-1)^(j-k)*binomial(n+j,2*j)*binomial(n+j,2*k) );
for(n=0,12, for(k=0,n, print1(T(n,k), ", "))) \\ G. C. Greubel, Aug 08 2019
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b=binomial; [[sum((-1)^(j-k)*b(n+j,2*j)*b(n+j,2*k) for j in (0..n)) for k in (0..n)] for n in (0..12)] # G. C. Greubel, Aug 08 2019
A123970
Triangle read by rows: T(0,0)=1; T(n,k) is the coefficient of x^(n-k) in the monic characteristic polynomial of the n X n matrix (min(i,j)) (i,j=1,2,...,n) (0 <= k <= n, n >= 1).
Original entry on oeis.org
1, 1, -1, 1, -3, 1, 1, -6, 5, -1, 1, -10, 15, -7, 1, 1, -15, 35, -28, 9, -1, 1, -21, 70, -84, 45, -11, 1, 1, -28, 126, -210, 165, -66, 13, -1, 1, -36, 210, -462, 495, -286, 91, -15, 1, 1, -45, 330, -924, 1287, -1001, 455, -120, 17, -1, 1, -55, 495, -1716, 3003, -3003, 1820, -680, 153, -19, 1, 1, -66, 715, -3003, 6435, -8008
Offset: 0
Triangular sequence (gives the odd Tutte-Beraha constants as roots!) begins:
1;
1, -1;
1, -3, 1;
1, -6, 5, -1;
1, -10, 15, -7, 1;
1, -15, 35, -28, 9, -1;
1, -21, 70, -84, 45, -11, 1;
1, -28, 126, -210, 165, -66, 13, -1;
1, -36, 210, -462, 495, -286, 91, -15, 1;
1, -45, 330, -924, 1287, -1001, 455, -120, 17, -1;
...
- S. Beraha, Infinite non-trivial families of maps and chromials, Ph.D. thesis. Baltimore, MD: Johns Hopkins University, 1975.
- Steven R. Finch, Mathematical Constants (Encyclopedia of Mathematics and its Applications), chapter 5.25.
- W. T. Tutte, "More about Chromatic Polynomials and the Golden Ratio." In Combinatorial Structures and their Applications: Proc. Calgary Internat. Conf., Calgary, Alberta, 1969. New York: Gordon and Breach, p. 439, 1969.
Modulo signs, inverse matrix to
A039599.
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/* As triangle */ [[(-1)^k*Binomial(n + k, 2*k): k in [0..n]]: n in [0.. 15]]; // Vincenzo Librandi, Jan 04 2019
-
with(linalg): m:=(i,j)->min(i,j): M:=n->matrix(n,n,m): T:=(n,k)->coeff(charpoly(M(n),x),x,n-k): 1; for n from 1 to 11 do seq(T(n,k),k=0..n) od; # yields sequence in triangular form
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An[d_] := MatrixPower[Table[Min[n, m], {n, 1, d}, {m, 1, d}], -1]; Join[{{1}}, Table[CoefficientList[CharacteristicPolynomial[An[d], x], x], {d, 1, 20}]]; Flatten[%]
A190909
Triangle read by rows: T(n,k) = binomial(n+k,n-k) * k! / floor(k/2)!^2.
Original entry on oeis.org
1, 1, 1, 1, 3, 2, 1, 6, 10, 6, 1, 10, 30, 42, 6, 1, 15, 70, 168, 54, 30, 1, 21, 140, 504, 270, 330, 20, 1, 28, 252, 1260, 990, 1980, 260, 140, 1, 36, 420, 2772, 2970, 8580, 1820, 2100, 70, 1, 45, 660, 5544, 7722, 30030, 9100, 16800, 1190, 630
Offset: 0
[0] 1
[1] 1, 1
[2] 1, 3, 2
[3] 1, 6, 10, 6
[4] 1, 10, 30, 42, 6
[5] 1, 15, 70, 168, 54, 30
[6] 1, 21, 140, 504, 270, 330, 20
[7] 1, 28, 252, 1260, 990, 1980, 260, 140
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A190909 := (n,k) -> binomial(n+k,n-k)*k!/iquo(k,2)!^2:
seq(print(seq(A190909(n,k),k=0..n)),n=0..7);
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Flatten[Table[Binomial[n+k,n-k] k!/(Floor[k/2]!)^2,{n,0,10},{k,0,n}]] (* Harvey P. Dale, Mar 25 2012 *)
A108367
L(n,-n), where L is defined as in A108299.
Original entry on oeis.org
1, -2, 5, -29, 265, -3191, 47321, -832040, 16908641, -389806471, 10049731549, -286482047279, 8946795882025, -303762892305614, 11140078609864049, -438857301101610929, 18482410314337295233, -828657053219851847135, 39406519321199703822581, -1981132660316876165976260
Offset: 0
-
a(n) = sum(k=0, n, (-1)^k*binomial(n+k,2*k)*(n+2)^k); \\ Jinyuan Wang, Feb 25 2020
A114192
Riordan array (1/(1-2x),x/(1-2x)^2).
Original entry on oeis.org
1, 2, 1, 4, 6, 1, 8, 24, 10, 1, 16, 80, 60, 14, 1, 32, 240, 280, 112, 18, 1, 64, 672, 1120, 672, 180, 22, 1, 128, 1792, 4032, 3360, 1320, 264, 26, 1, 256, 4608, 13440, 14784, 7920, 2288, 364, 30, 1, 512, 11520, 42240, 59136, 41184, 16016, 3640, 480, 34, 1
Offset: 0
Triangle begins
1;
2, 1;
4, 6, 1;
8, 24, 10, 1;
16, 80, 60, 14, 1;
32, 240, 280, 112, 18, 1;
Original entry on oeis.org
1, 1, 2, 6, 24, 122, 758, 5606, 48378, 479532, 5390940, 68022932, 954948752, 14804391270, 251815549396, 4673137101108, 94148342547146, 2050127343000170, 48061939075355080, 1208742383083994580, 32507565146820336836, 932149980847656487522, 28423646163259392354386, 919399182232129554488328
Offset: 0
Triangle A054142 begins:
1;
1, 1;
1, 3, 1;
1, 5, 6, 1;
1, 7, 15, 10, 1;
1, 9, 28, 35, 15, 1;
...
a(3) = 6 = 1*1 + 3*1 + 1*2
a(4) = 24 = 1*1 + 5*1 + 6*2 + 1*6
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A054142(n, k) = binomial(2*n-k, k);
a(n) = if (n==0, 1, sum(k=0, n-1, A054142(n-1,k)*a(k))); \\ too slow
lista(nn) = my(v=vector(nn)); v[1] = 1; for (n=2, nn, v[n] = sum(k=0, n-1, A054142(n-2,k)*v[k+1]);); v; \\ Michel Marcus, Jan 17 2025
A144252
Eigentriangle, row sums = A144251 shifted, right border = A144251.
Original entry on oeis.org
1, 1, 1, 1, 3, 2, 1, 5, 12, 6, 1, 7, 30, 60, 24, 1, 9, 56, 210, 360, 122, 1, 11, 90, 504, 1680, 2562, 758, 1, 13, 132, 990, 5040, 15372, 21224, 5606, 1, 15, 182, 1716, 11880, 36364, 159180, 201816, 47378, 1, 17, 240, 2730, 24024, 157014, 700392, 1849980, 2177010, 479532
Offset: 0
First few rows of the triangle =
1;
1, 1;
1, 3, 2;
1, 5, 12, 6;
1, 7, 30, 60, 24;
1, 9, 56, 210, 360, 122;
1, 11, 90, 504, 1680, 2562, 758;
1, 13, 132, 990, 5040, 15372, 21224, 5606;
...
The triangle is generated from A054142 and its own eigensequence, A144251.
Triangle A054142 =
1;
1, 1;
1, 3, 1;
1, 5, 6, 1;
1, 7, 15, 10, 1;
...
The eigensequence of A054142 = A144251: (1, 1, 2, 6, 24, 122, 758, 5606,...);
Example: row 3 of A144252 = (1, 5, 12, 6) = termwise products of (1, 5, 6, 1) and (1, 1, 2, 6) = (1*1, 5*1, 6*2, 1*6).
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A054142(n, k) = binomial(2*n-k, k);
V144251(nn) = my(v=vector(nn)); v[1] = 1; for (n=2, nn, v[n] = sum(k=0, n-1, A054142(n-2,k)*v[k+1]);); v;
row(n) = my(v=V144251(n+1)); vector(n+1, k, A054142(n,k-1) * v[k]); \\ Michel Marcus, Jan 18 2025
A166697
A "Morgan Voyce" transform of A103210.
Original entry on oeis.org
1, 4, 25, 187, 1552, 13771, 127927, 1228576, 12099751, 121538581, 1240336660, 12824049277, 134043231781, 1414108869268, 15037450664317, 161014687970191, 1734550886346592, 18785969304551263, 204432608804093155
Offset: 0
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A166697 := proc(n)
add(A166696(k),k=0..n) ;
end proc: # R. J. Mathar, Feb 10 2015
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CoefficientList[Series[(1 - 3*t + t^2 - Sqrt[1 - 14*t + 27*t^2 - 14*t^3 + t^4])/(4*t*(1 - t)), {t, 0, 50}], t] (* G. C. Greubel, May 23 2016 *)
A171822
Triangle T(n,k) = binomial(2*n-k, k)*binomial(n+k, 2*k), read by rows.
Original entry on oeis.org
1, 1, 1, 1, 9, 1, 1, 30, 30, 1, 1, 70, 225, 70, 1, 1, 135, 980, 980, 135, 1, 1, 231, 3150, 7056, 3150, 231, 1, 1, 364, 8316, 34650, 34650, 8316, 364, 1, 1, 540, 19110, 132132, 245025, 132132, 19110, 540, 1, 1, 765, 39600, 420420, 1288287, 1288287, 420420, 39600, 765, 1
Offset: 0
Triangle begins as:
1;
1, 1;
1, 9, 1;
1, 30, 30, 1;
1, 70, 225, 70, 1;
1, 135, 980, 980, 135, 1;
1, 231, 3150, 7056, 3150, 231, 1;
1, 364, 8316, 34650, 34650, 8316, 364, 1;
1, 540, 19110, 132132, 245025, 132132, 19110, 540, 1;
1, 765, 39600, 420420, 1288287, 1288287, 420420, 39600, 765, 1;
1, 1045, 75735, 1166880, 5465460, 9018009, 5465460, 1166880, 75735, 1045, 1;
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[Binomial(2*n-k, k)*Binomial(n+k, 2*k): k in [0..n], n in [0..10]]; // G. C. Greubel, Feb 22 2021
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Table[Binomial[2*n-k, k]*Binomial[n+k, 2*k], {n,0,10}, {k,0,n}]//Flatten
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flatten([[binomial(2*n-k, k)*binomial(n+k, 2*k) for k in (0..n)] for n in (0..10)]) # G. C. Greubel, Feb 22 2021
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