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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A064059 Seventh column of Catalan triangle A009766.

Original entry on oeis.org

132, 429, 1001, 2002, 3640, 6188, 9996, 15504, 23256, 33915, 48279, 67298, 92092, 123970, 164450, 215280, 278460, 356265, 451269, 566370, 704816, 870232, 1066648, 1298528, 1570800, 1888887, 2258739, 2686866, 3180372, 3746990, 4395118, 5133856, 5973044
Offset: 0

Views

Author

Wolfdieter Lang, Sep 13 2001

Keywords

Crossrefs

Cf. A000096, A005586, A005587, A005557 (third to sixth column).

Programs

  • Magma
    A064059:= func< n | (n+1)*Binomial(n+12,5)/6 >;
    [A064059(n): n in [0..40]]; // G. C. Greubel, Sep 27 2024
    
  • Maple
    [seq(binomial(n+1,6)-2*binomial(n,5),n=12..55)]; # Zerinvary Lajos, Jul 19 2006
  • Mathematica
    CoefficientList[Series[(42 z^5-252 z^4+616 z^3-770 z^2+495 z-132)/(z-1)^7, {z, 0, 200}], z] (* Vladimir Joseph Stephan Orlovsky, Jun 22 2011 *)
    LinearRecurrence[{7,-21,35,-35,21,-7,1},{132,429,1001,2002,3640,6188,9996},40] (* Harvey P. Dale, Jan 08 2025 *)
  • SageMath
    def A064059(n): return (n+1)*binomial(n+12,5)//6
    [A064059(n) for n in range(41)] # G. C. Greubel, Sep 27 2024

Formula

G.f.: (132-495*x+770*x^2-616*x^3+252*x^4-42*x^5)/(1-x)^7; numerator polynomial is N(2;5, x) from A062991.
a(n) = A009766(n+6, 6) = (n+1)*binomial(n+12,5)/6.
a(n) = binomial(n+13,6) - 2*binomial(n+12,5). - Zerinvary Lajos, Jul 19 2006
a(n) = A214292(n+11,5). - Reinhard Zumkeller, Jul 12 2012
From Amiram Eldar, Sep 06 2022: (Start)
Sum_{n>=0} 1/a(n) = 25961/2134440.
Sum_{n>=0} (-1)^n/a(n) = 4160*log(2)/77 - 79917773/2134440. (End)

A000590 a(n) = 13*binomial(2n,n-6)/(n+7).

Original entry on oeis.org

1, 13, 104, 663, 3705, 19019, 92092, 427570, 1924065, 8454225, 36463440, 154969620, 650872404, 2707475148, 11173706960, 45812198536, 186803188858, 758201178306, 3065415516592, 12352414499425, 49634247352235, 198954083924505, 795816335698020, 3177498557750790
Offset: 6

Views

Author

Keywords

Comments

Number of lattice paths from (0,0) to (n,n) with steps E=(1,0) and N=(0,1) which touch but do not cross the line x-y=6. - Herbert Kociemba, May 24 2004
Number of standard tableaux of shape (n+6,n-6). - Emeric Deutsch, May 30 2004

References

  • N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Programs

  • Mathematica
    a[n_] := 13*Binomial[2*n, n-6]/(n+7); Array[a, 24, 6] (* Amiram Eldar, Sep 26 2022 *)
  • PARI
    a(n) = 13*binomial(2*n,n-6)/(n+7); \\ Michel Marcus, Oct 16 2017

Formula

G.f.: x^6*C(x)^13, where C(x)=[1-sqrt(1-4x)]/(2x) is g.f. for the Catalan numbers (A000108). - Emeric Deutsch, May 30 2004
Let A be the Toeplitz matrix of order n defined by: A[i,i-1]=-1, A[i,j]=Catalan(j-i), (i<=j), and A[i,j]=0, otherwise. Then, for n>=12, a(n-6)=(-1)^(n-12)*coeff(charpoly(A,x),x^12). - Milan Janjic, Jul 08 2010
a(n) = A214292(2*n-1,n-7) for n > 6. - Reinhard Zumkeller, Jul 12 2012
-(n+7)*(n-6)*a(n) + 2*n*(2*n-1)*a(n-1) = 0. - R. J. Mathar, Jun 20 2013
From Amiram Eldar, Sep 26 2022: (Start)
Sum_{n>=6} 1/a(n) = 16777/5460 - 128*Pi/(117*sqrt(3)).
Sum_{n>=6} (-1)^n/a(n) = 787536*log(phi)/(325*sqrt(5)) - 14210999/27300, where phi is the golden ratio (A001622). (End)

A005557 Number of walks on square lattice.

Original entry on oeis.org

42, 132, 297, 572, 1001, 1638, 2548, 3808, 5508, 7752, 10659, 14364, 19019, 24794, 31878, 40480, 50830, 63180, 77805, 95004, 115101, 138446, 165416, 196416, 231880, 272272, 318087, 369852, 428127, 493506, 566618, 648128, 738738, 839188, 950257, 1072764
Offset: 0

Views

Author

Keywords

References

  • N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Crossrefs

Sixth diagonal of Catalan triangle A033184.
Sixth column of Catalan triangle A009766.

Programs

  • GAP
    List([0..30],n->(n+1)*Binomial(n+10,4)/5); # Muniru A Asiru, Apr 10 2018
    
  • Magma
    [(n+1)*Binomial(n+10, 4)/5: n in [0..40]]; // Vincenzo Librandi, Mar 20 2013
    
  • Maple
    [seq(binomial(n,5)-binomial(n,3),n=9..55)]; # Zerinvary Lajos, Jul 19 2006
    A005557:=(42-120*z+135*z**2-70*z**3+14*z**4)#(z-1)**6; # conjectured by Simon Plouffe in his 1992 dissertation
  • Mathematica
    CoefficientList[Series[(14 z^4 - 70 z^3 + 135 z^2 - 120 z + 42)/(z - 1)^6, {z, 0, 200}], z] (* Vladimir Joseph Stephan Orlovsky, Jun 22 2011 *)
    LinearRecurrence[{6,-15,20,-15,6,-1},{42,132,297,572,1001,1638},40] (* Harvey P. Dale, Feb 22 2024 *)
  • PARI
    a(n)=(n+1)*binomial(n+10,4)/5 \\ Charles R Greathouse IV, Oct 21 2022

Formula

a(n) = A009766(n+5, 5) = (n+1)*binomial(n+10, 4)/5.
G.f.: (42 - 120*x + 135*x^2 - 70*x^3 + 14*x^4)/(1-x)^6; numerator polynomial is N(2;4, x) from A062991.
a(n) = binomial(n+9,5) - binomial(n+9,3). - Zerinvary Lajos, Jul 19 2006
a(n) = A214292(n+9, 4). - Reinhard Zumkeller, Jul 12 2012
From Amiram Eldar, Sep 06 2022: (Start)
Sum_{n>=0} 1/a(n) = 2509/63504.
Sum_{n>=0} (-1)^n/a(n) = 951395/63504 - 1360*log(2)/63. (End)

Extensions

More terms and formula from Wolfdieter Lang, Sep 04 2001

A064061 Eighth column of Catalan triangle A009766.

Original entry on oeis.org

429, 1430, 3432, 7072, 13260, 23256, 38760, 62016, 95931, 144210, 211508, 303600, 427570, 592020, 807300, 1085760, 1442025, 1893294, 2459664, 3164480, 4034712, 5101360, 6399888, 7970688, 9859575, 12118314, 14805180, 17985552, 21732542, 26127660, 31261516
Offset: 0

Views

Author

Wolfdieter Lang, Sep 13 2001

Keywords

Crossrefs

Cf. A009766, A064059 (seventh column), A062991, A214292.

Programs

  • Magma
    A064061:= func< n | (n+1)*Binomial(n+14, 6)/7 >;
    [A064061(n): n in [0..40]]; // G. C. Greubel, Sep 28 2024
    
  • Maple
    [seq(binomial(n,7)-binomial(n,5),n=13..37)]; # Zerinvary Lajos, Nov 25 2006
  • Mathematica
    CoefficientList[Series[(132*z^6 - 924*z^5 + 2730*z^4 - 4368*z^3 + 4004*z^2 - 2002*z + 429)/(z - 1)^8, {z, 0, 100}], z] (* Vladimir Joseph Stephan Orlovsky, Jul 16 2011 *)
    Table[Binomial[n,7]-Binomial[n,5],{n,13,50}] (* or *) LinearRecurrence[ {8,-28,56,-70,56,-28,8,-1},{429,1430,3432,7072,13260,23256,38760,62016},40] (* Harvey P. Dale, Sep 03 2015 *)
  • SageMath
    def A064061(n): return (n+1)*binomial(n+14,6)//7
    [A064061(n) for n in range(41)] # G. C. Greubel, Sep 28 2024

Formula

a(n) = A009766(n+7, 7) = (n+1)*binomial(n+14, 6)/7.
G.f.: (429-2002*x+4004*x^2-4368*x^3+2730* x^4-924*x^5+132*x^6)/(1-x)^8; numerator polynomial is N(2;6, x) from A062991.
a(n) = C(n+13,7) - C(n+13,5). - Zerinvary Lajos, Nov 25 2006
a(n) = A214292(n+13,6). - Reinhard Zumkeller, Jul 12 2012
From Amiram Eldar, Sep 06 2022: (Start)
Sum_{n>=0} 1/a(n) = 323171/88339680.
Sum_{n>=0} (-1)^n/a(n) = 7929257917/88339680 - 55552*log(2)/429. (End)

A129936 a(n) = (n-2)*(n+3)*(n+2)/6.

Original entry on oeis.org

-2, -2, 0, 5, 14, 28, 48, 75, 110, 154, 208, 273, 350, 440, 544, 663, 798, 950, 1120, 1309, 1518, 1748, 2000, 2275, 2574, 2898, 3248, 3625, 4030, 4464, 4928, 5423, 5950, 6510, 7104, 7733, 8398, 9100, 9840, 10619, 11438, 12298, 13200, 14145, 15134, 16168, 17248
Offset: 0

Views

Author

Roger L. Bagula, Jun 09 2007

Keywords

Comments

Essentially the same as A005586.

Crossrefs

Programs

  • Maple
    seq(sum(i*(k-i+1), i=1..k+2), k=0..99); # Wesley Ivan Hurt, Sep 21 2013
  • Mathematica
    f[n_] = Binomial[n + 3, 3] - (n + 3)*(n + 2)/2; Table[f[n], {n, 0, 30}]
    LinearRecurrence[{4,-6,4,-1},{-2,-2,0,5},50] (* Harvey P. Dale, Jul 03 2020 *)
  • PARI
    a(n)=(n-2)*(n+3)*(n+2)/6 \\ Charles R Greathouse IV, Oct 07 2015

Formula

a(n) = binomial(n+3,3) - (n + 3)*(n + 2)/2.
a(n) = A214292(n+2,2). - Reinhard Zumkeller, Jul 12 2012
G.f.: (x^3-4*x^2+6*x-2)/(x-1)^4. - Colin Barker, Sep 05 2012
From Wesley Ivan Hurt, Sep 21 2013: (Start)
a(n) = Sum_{i=1..n+2} i*(n-i+1).
a(n+2) = A000292(n+1) + A034856(n), n>0. (End)
From Amiram Eldar, Sep 26 2022: (Start)
Sum_{n>=3} 1/a(n) = 77/200.
Sum_{n>=3} (-1)^(n+1)/a(n) = 363/200 - 12*log(2)/5. (End)
From Elmo R. Oliveira, Aug 04 2025: (Start)
E.g.f.: exp(x)*(x^3 + 6*x^2 - 12)/6.
a(n) = A023444(n)*A002378(n+2)/6.
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4). (End)

Extensions

More terms from Wesley Ivan Hurt, Sep 21 2013

A090749 a(n) = 12 * C(2n+1,n-5) / (n+7).

Original entry on oeis.org

1, 12, 90, 544, 2907, 14364, 67298, 303600, 1332045, 5722860, 24192090, 100975680, 417225900, 1709984304, 6962078952, 28192122176, 113649492522, 456442180920, 1827459250276, 7297426411968, 29075683360185, 115631433392020, 459124809056550, 1820529677650320, 7210477496434485
Offset: 5

Views

Author

Philippe Deléham, Feb 15 2004

Keywords

Comments

Also a diagonal of A059365 and A009766. See also A000108, A002057, A003517, A003518, A003519.
Number of standard tableaux of shape (n+6,n-5). - Emeric Deutsch, May 30 2004

Crossrefs

Programs

  • Mathematica
    Table[12*Binomial[2*n + 1, n - 5]/(n + 7), {n,5,50}] (* G. C. Greubel, Feb 07 2017 *)
  • PARI
    for(n=5,50, print1(12*binomial(2*n+1,n-5)/(n+7), ", ")) \\ G. C. Greubel, Feb 07 2017

Formula

a(n) = A039598(n, 5) = A033184(n+7, 12).
G.f.: x^5*C(x)^12 with C(x) g.f. of A000108(Catalan).
Let A be the Toeplitz matrix of order n defined by: A[i,i-1]=-1, A[i,j]=Catalan(j-i), (i<=j), and A[i,j]=0, otherwise. Then, for n>=11, a(n-6)=(-1)^(n-11)*coeff(charpoly(A,x),x^11). - Milan Janjic, Jul 08 2010
a(n) = A214292(2*n,n-6) for n > 5. - Reinhard Zumkeller, Jul 12 2012
From Karol A. Penson, Nov 21 2016: (Start)
O.g.f.: z^5 * 4^6/(1+sqrt(1-4*z))^12.
Recurrence: (-4*(n-5)^2-58*n+80)*a(n+1)-(-n^2-6*n+27)*a(n+2)=0, a(0),a(1),a(2),a(3),a(4)=0,a(5)=1,a(6)=12, n>=5.
Asymptotics: (-903+24*n)*4^n*sqrt(1/n)/(sqrt(Pi)*n^2).
Integral representation as n-th moment of a signed function W(x) on x=(0,4),in Maple notation: a(n+5)=int(x^n*W(x),x=0..4),n=0,1,..., where W(x)=(256/231)*sqrt(4-x)*JacobiP(5, 1/2, 1/2, (1/2)*x-1)*x^(11/2)/Pi and JacobiP are Jacobi polynomials. Note that W(0)=W(4)=0. (End).
From Ilya Gutkovskiy, Nov 21 2016: (Start)
E.g.f.: 6*exp(2*x)*BesselI(6,2*x)/x.
a(n) ~ 3*2^(2*n+3)/(sqrt(Pi)*n^(3/2)). (End)
From Amiram Eldar, Sep 26 2022: (Start)
Sum_{n>=5} 1/a(n) = 88699/15120 - 71*Pi/(27*sqrt(3)).
Sum_{n>=5} (-1)^(n+1)/a(n) = 102638*log(phi)/(75*sqrt(5)) - 22194839/75600, where phi is the golden ratio (A001622). (End)

Extensions

Missing term 113649492522 inserted by Ilya Gutkovskiy, Dec 07 2016

A259525 First differences of A007318, when Pascal's triangle is seen as flattened list.

Original entry on oeis.org

0, 0, 0, 1, -1, 0, 2, 0, -2, 0, 3, 2, -2, -3, 0, 4, 5, 0, -5, -4, 0, 5, 9, 5, -5, -9, -5, 0, 6, 14, 14, 0, -14, -14, -6, 0, 7, 20, 28, 14, -14, -28, -20, -7, 0, 8, 27, 48, 42, 0, -42, -48, -27, -8, 0, 9, 35, 75, 90, 42, -42, -90, -75, -35, -9, 0, 10, 44, 110
Offset: 0

Views

Author

Reinhard Zumkeller, Jul 18 2015

Keywords

Comments

A214292 gives first differences per row in Pascal's triangle.

Crossrefs

Programs

  • Haskell
    a259525 n = a259525_list !! n
    a259525_list = zipWith (-) (tail pascal) pascal
                               where pascal = concat a007318_tabl
    
  • Magma
    [k eq n select 0 else (n-2*k-1)*Binomial(n,k+1)/(n-k): k in [0..n], n in [0..14]]; // G. C. Greubel, Apr 25 2024
    
  • Mathematica
    Table[If[k==n, 0, ((n-2*k-1)/(n-k))*Binomial[n,k+1]], {n,0,12}, {k,0, n}]//Flatten (* G. C. Greubel, Apr 25 2024 *)
  • SageMath
    flatten([[binomial(n,k+1) -binomial(n,k) +int(k==n) for k in range(n+1)] for n in range(15)]) # G. C. Greubel, Apr 25 2024

Formula

From G. C. Greubel, Apr 25 2024: (Start)
If viewed as a triangle then:
T(n, k) = binomial(n, k+1) - binomial(n, k), with T(n, n) = 0.
T(n, n-k) = - T(n, k), for 0 <= k < n.
T(2*n, n) = [n=0] - A000108(n).
Sum_{k=0..n} T(n, k) = 0 (row sums).
Sum_{k=0..floor(n/2)} T(n, k) = A047171(n).
Sum_{k=0..n} (-1)^k*T(n, k) = A021499(n).
Sum_{k=0..floor(n/2)} T(n-k, k) = A074331(n-1). (End)

A124087 9th column of Catalan triangle A009766.

Original entry on oeis.org

1430, 4862, 11934, 25194, 48450, 87210, 149226, 245157, 389367, 600875, 904475, 1332045, 1924065, 2731365, 3817125, 5259150, 7152444, 9612108, 12776588, 16811300, 21912660, 28312548, 36283236, 46142811, 58261125, 73066305, 91051857, 112784399, 138912059
Offset: 15

Views

Author

Zerinvary Lajos, Nov 25 2006

Keywords

Crossrefs

Programs

  • Maple
    [seq(binomial(n,8)-binomial(n,6),n=15..45)];
  • Mathematica
    CoefficientList[Series[(429*z^7 - 3432*z^6 + 11880*z^5 - 23100*z^4 + 27300*z^3 - 19656*z^2 + 8008*z - 1430)/(z - 1)^9, {z, 0, 100}], z] (* Vladimir Joseph Stephan Orlovsky, Jul 16 2011 *)
    Table[Binomial[n,8]-Binomial[n,6],{n,15,60}] (* or *) LinearRecurrence[ {9,-36,84,-126,126,-84,36,-9,1},{1430,4862,11934,25194,48450,87210,149226,245157,389367},30] (* Harvey P. Dale, Apr 15 2017 *)

Formula

a(n) = C(n,8)-C(n,6).
a(n) = A214292(n+15,7). - Reinhard Zumkeller, Jul 12 2012
From Amiram Eldar, Sep 06 2022: (Start)
Sum_{n>=15} 1/a(n) = 12515/11594583.
Sum_{n>=15} (-1)^(n+1)/a(n) = 1942528*log(2)/6435 - 60651032147/289864575. (End)

A124088 10th column of Catalan triangle A009766.

Original entry on oeis.org

4862, 16796, 41990, 90440, 177650, 326876, 572033, 961400, 1562275, 2466750, 3798795, 5722860, 8454225, 12271350, 17530500, 24682944, 34295052, 47071640, 63882940, 85795600, 114108148, 150391384, 196534195, 254795320, 327861625, 418913482, 531697881
Offset: 17

Views

Author

Zerinvary Lajos, Nov 25 2006

Keywords

Crossrefs

Programs

  • Maple
    [seq(binomial(n,9)-binomial(n,7),n=17..42)];
  • Mathematica
    CoefficientList[Series[(1430*z^8 - 12870*z^7 + 51051*z^6 - 116688*z^5 + 168300*z^4 - 157080*z^3 + 92820*z^2 - 31824*z + 4862)/(z - 1)^10, {z, 0, 100}], z] (* Vladimir Joseph Stephan Orlovsky, Jul 16 2011 *)

Formula

a(n) = C(n,9)-C(n,7).
a(n) = A214292(n+17,8). - Reinhard Zumkeller, Jul 12 2012
From Amiram Eldar, Sep 06 2022: (Start)
Sum_{n>=17} 1/a(n) = 2074783/6618932320.
Sum_{n>=17} (-1)^(n+1)/a(n) = 2259208566291/4727808800 - 8379648*log(2)/12155. (End)

A128634 Number of parallel permutations of length n.

Original entry on oeis.org

0, 2, 8, 26, 82, 262, 856, 2858, 9722, 33590, 117570, 416022, 1485798, 5348878, 19389688, 70715338, 259289578, 955277398, 3534526378, 13128240838, 48932534038, 182965127278, 686119227298, 2579808294646, 9723892802902, 36734706144302, 139067101832006, 527495903500718
Offset: 1

Views

Author

Ralf Stephan, May 08 2007

Keywords

Crossrefs

Programs

  • GAP
    List([1..30], n-> 2*(Binomial(2*n, n)/(n+1) -1) ); # G. C. Greubel, Dec 02 2019
  • Magma
    [2*(Catalan(n)-1): n in [1..40]]; // Vincenzo Librandi, Jul 22 2015
    
  • Maple
    c:=binomial(2*n,n)/(n+1); seq(2*(c(n)-1), n=1..30); # G. C. Greubel, Dec 02 2019
  • Mathematica
    Table[2 (CatalanNumber[n] - 1), {n, 30}] (* Vincenzo Librandi, Jul 22 2015 *)
  • PARI
    vector(30, n, 2*(binomial(2*n,n)/(n+1) -1) ) \\ Michel Marcus, Jul 21 2015
    
  • Sage
    [2*(catalan_number(n) -1) for n in (1..30)] # G. C. Greubel, Dec 02 2019
    

Formula

a(n) = -2 + 2 * binomial(2*n,n)/(n+1).
a(n) = -2 + A068875(n+1).
a(n) = 2*A001453(n) for n > 1. - J. M. Bergot, Sep 03 2013
a(n)= Sum_{r=0..n} A214292(n, r)^2. - J. M. Bergot, Sep 04 2013

Extensions

More terms from Michel Marcus, Jul 21 2015
Offset changed by G. C. Greubel, Dec 02 2019
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