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 1-7 of 7 results.

A215002 Number of all solid standard Young tableaux of shape [[n,k],[n-k]] for 0<=k<=n.

Original entry on oeis.org

1, 2, 10, 60, 398, 2764, 19796, 144536, 1070294, 8007052, 60380940, 458185992, 3494554380, 26764583096, 205711091880, 1585822364592, 12256625999718, 94942581080204, 736895626109148, 5729374337686696, 44615143884080996, 347905737091032552, 2716349710039969688
Offset: 0

Views

Author

Alois P. Heinz, Jul 30 2012

Keywords

Crossrefs

Row sums of A214775.

Programs

  • Maple
    b:= proc(x, y, z) option remember; `if`(z>y, b(x, z, y),
          `if`({x, y, z}={0}, 1, `if`(x>y and x>z, b(x-1, y, z), 0)+
          `if`(y>0, b(x, y-1, z), 0)+ `if`(z>0, b(x, y, z-1), 0)))
        end:
    a:= n-> add(b(n, k, n-k), k=0..n):
    seq(a(n), n=0..25);
    # second Maple program:
    a:= proc(n) option remember; `if`(n<4, [1, 2, 10, 60][n+1],
          ((1640*n^8 -1180*n^7 -7114*n^6 +5615*n^5 +20240*n^4 -35170*n^3
           +20379*n^2 -4050*n) *a(n-1) +(-7640*n^8 +14560*n^7 +47374*n^6
           -140900*n^5 -37160*n^4 +601810*n^3 -944154*n^2 +580680*n -113400)
           *a(n-2) +(-28800*n^8 +181440*n^7 -138240*n^6 -874800*n^5 +670680*n^4
           +3165480*n^3 -3646440*n^2 -12960*n -453600) *a(n-3) +(207360*n^8
           -1451520*n^7 +912384*n^6 +11767680*n^5 -15720480*n^4 -42042240*n^3
           +92516256*n^2 -50388480*n +16329600) *a(n-4)) / (n* (n+1) *(2*n-1)
           *(2*n+1) *(20*n^4-47*n^2-33*n+90)))
        end:
    seq(a(n), n=0..25);
  • Mathematica
    b[x_, y_, z_] := b[x, y, z] = If[z>y, b[x, z, y], If[Union[{x, y, z}] == {0}, 1, If[x>y && x>z, b[x-1, y, z], 0] + If[y>0, b[x, y-1, z], 0] + If[z>0, b[x, y, z-1], 0]]]; T[n_, k_] := b[n, k, n-k]; a[n_] := Sum[T[n, k], {k, 0, n}]; Table[a[n], {n, 0, 22}] (* Jean-François Alcover, Feb 05 2015, after Alois P. Heinz *)

Formula

See Maple programs.
a(n) ~ sqrt((5*sqrt(5))/2-11/2) * 8^n / sqrt(Pi*n). - Vaclav Kotesovec, Jul 16 2014

A214801 Number of solid standard Young tableaux of shape [[2*n,n],[n]].

Original entry on oeis.org

1, 6, 174, 7020, 325590, 16290708, 854630476, 46305862488, 2568272967270, 144984584562180, 8298621602461476, 480298712286979560, 28052543639835133692, 1650956086756046986440, 97790578929910135588440, 5824509559447044190027952, 348581174512709008160833158
Offset: 0

Views

Author

Alois P. Heinz, Jul 28 2012

Keywords

Crossrefs

Central row elements of A214775.
Column k=2 of A176129.

Programs

  • Maple
    b:= proc(x, y, z) option remember; `if`(z>y, b(x, z, y),
          `if`({x, y, z}={0}, 1, `if`(x>y and x>z, b(x-1, y, z), 0)+
          `if`(y>0, b(x, y-1, z), 0)+ `if`(z>0, b(x, y, z-1), 0)))
        end:
    a:= n-> b(2*n, n, n):
    seq(a(n), n=0..20);
  • Mathematica
    b[x_, y_, z_] := b[x, y, z] = If[z>y, b[x, z, y], If[Union[{x, y, z}] == {0}, 1, If[x>y && x>z, b[x-1, y, z], 0] + If[y>0, b[x, y-1, z], 0] + If[z>0, b[x, y, z-1], 0]]]; a[n_] := b[2n, n, n]; Table[a[n], {n, 0, 16}] (* Jean-François Alcover, Feb 05 2015, after Alois P. Heinz *)

Formula

Recurrence: (n-1)*n^2*(2*n-1)*(2*n+1)*(4*n-1)*(4*n+1)*(392*n^4 - 2044*n^3 + 4216*n^2 - 3944*n + 1377)*a(n) = 2*(n-1)*(1859648*n^10 - 13670048*n^9 + 43255264*n^8 - 75152192*n^7 + 75863336*n^6 - 41825576*n^5 + 7317576*n^4 + 5067372*n^3 - 3441344*n^2 + 785094*n - 59535)*a(n-1) - 4*(2*n-3)*(4*n-7)*(4*n-5)*(1310848*n^8 - 7998592*n^7 + 19695952*n^6 - 24269488*n^5 + 15125236*n^4 - 3514192*n^3 - 1066614*n^2 + 533457*n - 45927)*a(n-2) + 5184*n*(2*n-5)*(2*n-3)*(4*n-11)*(4*n-9)*(4*n-7)*(4*n-5)*(392*n^4 - 476*n^3 + 436*n^2 - 76*n - 3)*a(n-3). - Vaclav Kotesovec, Aug 31 2014
a(n) ~ sqrt((5*sqrt(5)-11)/4) * 64^n / (Pi*n). - Vaclav Kotesovec, Aug 31 2014

A214955 Number of solid standard Young tableaux of shape [[n,n-1],[1]].

Original entry on oeis.org

1, 6, 25, 98, 378, 1452, 5577, 21450, 82654, 319124, 1234506, 4784276, 18572500, 72209880, 281150505, 1096087770, 4278278070, 16717354500, 65388738030, 256000696380, 1003116947820, 3933750236520, 15437682614250, 60625494924228, 238235373671148, 936735006679752
Offset: 1

Views

Author

Alois P. Heinz, Jul 30 2012

Keywords

Comments

a(n) is odd if and only if n = 2^i-1 for i in {1, 2, 3, ...} = A000027.
Form an array with m(1,n) = n*(n+1)/2, m(n,1) = n*(n-1)+1, and m(i,j) = m(i,j-1) + m(i-1,j); A000217 in the top row, A002061 in the first column, A086514 in the second column. Then on the diagonal m(n,n) = a(n). - J. M. Bergot, May 02 2013

Crossrefs

Column k=1 of A214775.

Programs

  • Maple
    a:= proc(n) option remember;
          `if`(n<2, n, 2*(2*n-1)^2*a(n-1)/((n+1)*(2*n-3)))
        end:
    seq(a(n), n=1..30);
  • Mathematica
    a[n_]:= a[n] = If[n<2, n, 2*(2*n-1)^2*a[n-1]/((n+1)*(2*n-3))]; Array[a, 30] (* Jean-François Alcover, Aug 14 2017, translated from Maple *)
  • PARI
    a(n) = (2*n-1) * binomial(2*n,n)/(n+1); \\ Michel Marcus, Mar 06 2022

Formula

a(n) = 2*(2*n-1)^2/((n+1)*(2*n-3)) * a(n-1) for n>1; a(1) = 1.
a(n) = (2*n-1) * C(2*n,n)/(n+1) = A060747(n) * A000108(n).
a(n) = [x^n] x*(1 + 2*x)/(1 - x)^(n+2). - Ilya Gutkovskiy, Oct 12 2017
Sum_{n>=1} 1/a(n) = 1/6 + G + 13*Pi/(36*sqrt(3)) - Pi*log(2+sqrt(3))/8, where G is Catalan's constant (A006752). - Amiram Eldar, Mar 06 2022
From Stefano Spezia, Mar 29 2023: (Start)
O.g.f.: 1 + (3 - 3*sqrt(1 - 4*x) - 8*x)/(2*x*sqrt(1 - 4*x)).
E.g.f.: 1 + exp(2*x)*(3*I_1(2*x) - I_0(2*x)), where I_n(x) is the modified Bessel function of the first kind.
a(n) ~ 2^(1+2*n)/sqrt(n*Pi). (End)

A215298 Number of solid standard Young tableaux of shape [[n,n-2],[2]].

Original entry on oeis.org

2, 25, 174, 962, 4804, 22689, 103510, 461318, 2021916, 8752042, 37520972, 159633060, 674969224, 2839400945, 11893509990, 49637986590, 206519808300, 856904298030, 3547095101220, 14652264350940, 60412895258040, 248675669866650, 1022088942267900, 4195255959533052
Offset: 2

Views

Author

Alois P. Heinz, Aug 07 2012

Keywords

Crossrefs

Column k=2 of A214775.
Cf. A215002.

Programs

  • Maple
    a:= proc(n) option remember; `if`(n=2, 2,
          2*(4*n^5 -26*n^4 +60*n^3 -58*n^2 +22*n -5)*a(n-1)/
            (2*n^5 -14*n^4 +30*n^3 -10*n^2 -31*n +25))
        end:
    seq(a(n), n=2..30);
  • Mathematica
    Table[12*(1 - 4*n + 10*n^2 - 8*n^3 + 2*n^4) * (2*n-4)! / ((n-2)! * (n+1)!), {n, 2, 20}] (* Vaclav Kotesovec, Sep 02 2014 *)

Formula

See Maple program.
a(n) ~ 3 * 2^(2*n-1) * sqrt(n) / sqrt(Pi). - Vaclav Kotesovec, Sep 02 2014
a(n) = 12*(1 - 4*n + 10*n^2 - 8*n^3 + 2*n^4) * (2*n-4)! / ((n-2)! * (n+1)!). - Vaclav Kotesovec, Sep 02 2014

A215299 Number of solid standard Young tableaux of shape [[n,n-3],[3]].

Original entry on oeis.org

5, 98, 962, 7020, 43573, 245962, 1305238, 6633172, 32649890, 156817044, 738717796, 3425580376, 15679951989, 70992594650, 318450985230, 1417072222020, 6261985407990, 27502477286460, 120137081521500, 522256720264680, 2260525598620770, 9746264904755652
Offset: 3

Views

Author

Alois P. Heinz, Aug 07 2012

Keywords

Crossrefs

Column k=3 of A214775.
Cf. A215002.

Programs

  • Maple
    a:= proc(n) option remember; `if`(n<5, [0$2, 5, 98][n],
          2*(32*n^7 -400*n^6 +1976*n^5 -4900*n^4 +6452*n^3 -4420*n^2
          +1350*n-315)*a(n-1) / (16*n^7 -224*n^6 +1204*n^5 -3008*n^4
          +2980*n^3 +1072*n^2 -4155*n +2205))
        end:
    seq(a(n), n=3..30);
  • Mathematica
    Flatten[{5, Table[(8*(45 - 180*n + 580*n^2 - 756*n^3 + 484*n^4 - 144*n^5 + 16*n^6) * (2*n-6)!) / (3*(n-3)!*(n+1)!), {n, 4, 20}]}] (* Vaclav Kotesovec, Sep 02 2014 *)

Formula

See Maple program.
For n > 3, a(n) = (8*(45 - 180*n + 580*n^2 - 756*n^3 + 484*n^4 - 144*n^5 + 16*n^6) * (2*n-6)!) / (3 * (n-3)! * (n+1)!). - Vaclav Kotesovec, Sep 02 2014

A215300 Number of solid standard Young tableaux of shape [[n,n-4],[4]].

Original entry on oeis.org

14, 378, 4804, 43573, 325590, 2149454, 13054108, 74688594, 408634828, 2159302420, 11097147528, 55747502501, 274790652518, 1332928973766, 6377276361900, 30149660760870, 141057202034340, 653892592144620, 3006490865152440, 13722387184879650, 62220533305358076
Offset: 4

Views

Author

Alois P. Heinz, Aug 07 2012

Keywords

Crossrefs

Column k=4 of A214775.
Cf. A215002.

Programs

  • Maple
    a:= proc(n) option remember; `if`(n<6, [0$3, 14, 378, 4804][n],
          ((-460961029024*n^4 +54902186125572*n^3 -347074341314956*n^2
           +421934757637074*n +6838164520124) *a(n-1) +(104238656896016*n^4
           -2317913124589048*n^3 +16535317231755832*n^2 -44274446438628908*n
           +29901662719961532)*a(n-2) +(-391233321452352*n^4
           +7447800734464704*n^3 -48294258553516272*n^2 +122447135865649584*n
           -105955729051546080)*a(n-3)) / (286655151052*n^4 -1210962058579*n^3
           +4322649356693*n^2 -24951473774234*n -30771740340558))
        end:
    seq(a(n), n=4..30);
  • Mathematica
    Flatten[{14,Table[(2*(n-5))!/(3*(n-5)!*(n+1)!)*(160*(-567+2394*n-8862*n^2+15592*n^3-15484*n^4+9152*n^5-3292*n^6+704*n^7-82*n^8+4*n^9)),{n,5,20}]}] (* Vaclav Kotesovec, Sep 02 2014 *)

Formula

See Maple program.
For n > 4, a(n) = (2*(n-5))!/(3*(n-5)!*(n+1)!)*(160*(-567 + 2394*n - 8862*n^2 + 15592*n^3 - 15484*n^4 + 9152*n^5 - 3292*n^6 + 704*n^7 - 82*n^8 + 4*n^9)). - Vaclav Kotesovec, Sep 02 2014

A215301 Number of solid standard Young tableaux of shape [[n,n-5],[5]].

Original entry on oeis.org

42, 1452, 22689, 245962, 2149454, 16290708, 111709178, 711996820, 4292788212, 24777783256, 138077129921, 747501664986, 3949741123174, 20444004524804, 103955714523390, 520494659493180, 2570907398453580, 12546842041060200, 60579487688891610, 289692893191143876
Offset: 5

Views

Author

Alois P. Heinz, Aug 07 2012

Keywords

Crossrefs

Column k=5 of A214775.
Cf. A215002.

Programs

  • Maple
    a:=proc(n) option remember; `if`(n<7, [0$4, 42, 1452, 22689][n],
       ((-940984202308081409937789248*n^7+36378423601372783158274124928*n^6
        -540987251973268278464961515672*n^5+4140452478540141056223108638628*n^4
        -17643038551017281385645661643624*n^3+40489345935054116443261823323140*n^2
        -39934974057986427003556989745680*n-247683783218781902433156798480)*a(n-1)
        +(5038765510419498883689330496*n^7-154613008671019208064714735488*n^6
        +1939670093038831522623368803072*n^5-12888788321486668402366527701360*n^4
    +48941495657518683977159471709724*n^3-105016281014420890409086708155812*n^2
        +113403222542936117699329884355248*n-47046838608769352958257951122560)
        *a(n-2))/(79676793824198327746135844*n^7-1949805875384464242394656236*n^6
        +20900166698905174940775960603*n^5-125515785015357799830976856812*n^4
        +431332553464051479008795376439*n^3-723271251684163430971195319466*n^2
        +59211568171613916060478086240*n+1362260807703300463382362391640))
       end:
    seq(a(n), n=5..30);
  • Mathematica
    Flatten[{42, 1452, Table[(2*(n-6))! / (5 * (n-6)! * (n+1)!) * 64 * (-51975 + 217350*n - 873908*n^2 + 1738396*n^3 - 2038350*n^4 + 1500940*n^5 - 724004*n^6 + 231788*n^7 - 48750*n^8 + 6460*n^9 - 488*n^10 + 16*n^11), {n, 7, 20}]}]

Formula

See Maple program.
For n > 6, a(n) = (2*(n-6))! / (5 * (n-6)! * (n+1)!) * 64 * (-51975 + 217350*n - 873908*n^2 + 1738396*n^3 - 2038350*n^4 + 1500940*n^5 - 724004*n^6 + 231788*n^7 - 48750*n^8 + 6460*n^9 - 488*n^10 + 16*n^11). - Vaclav Kotesovec, Sep 02 2014
Showing 1-7 of 7 results.