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.

Previous Showing 11-17 of 17 results.

A082424 Coefficient of s(2n) in s(n,n) * s(n,n) * s(n,n) * s(n,n) * s(n,n) * s(n,n), where s(n,n) is the Schur function indexed by two parts of size n, s(2n) is the Schur function corresponding to the trivial representation and * represents the inner or Kronecker product.

Original entry on oeis.org

1, 1, 11, 41, 320, 1917, 14582, 100562, 688427, 4380888, 26324611, 148136566, 785175771, 3925637781, 18586683128, 83578440418, 358079558873, 1465784048253, 5748270468573, 21649265291143, 78483868584001
Offset: 0

Views

Author

Mike Zabrocki, Apr 24 2003

Keywords

References

  • I. G. Macdonald, Symmetric Functions and Hall Polynomials, Oxford Mathematical Monographs, Oxford Univ. Press, second edition, 1995.

Crossrefs

Cf. A008763 change 6 to 4 in the above program.

Programs

  • Maple
    compsclr := proc(k) local gamma; add( combinat[Chi]( [k,k], gamma)^6/ZEE(gamma),gamma= combinat[partition](2*k)); end: ZEE := proc (mu) local res, m, i; m := 1; res := convert(mu,`*`); for i from 2 to nops(mu) do if mu[i] <> mu[i-1] then m := 1 else m := m+1 fi; res := res*m; od; res; end:

Formula

a(n) = Sum_{gamma} Chi^{(n, n)}( gamma )^6/z(gamma) the sum is over all partitions gamma of 2n Chi^lambda(gamma) is the value of the symmetric group character z(gamma) is the size of the stablizer of the conjugacy class of symmetric group indexed by the partition gamma

A082437 Coefficient of s(2n) in s(n,n) * s(n,n) * s(n,n) * s(n,n) * s(n,n), where s(2n) is the Schur function corresponding to the trivial representation, s(n,n) is a Schur function corresponding two the two row partition and * represents the inner or Kronecker product of symmetric functions.

Original entry on oeis.org

1, 0, 5, 1, 36, 15, 228, 231, 1313, 1939, 6971, 11899, 33118, 59543, 140620, 254476, 538042, 959028, 1871808, 3258512, 5981444, 10140360, 17726166, 29257848, 49127549, 79032258, 128267727, 201437596
Offset: 0

Views

Author

Mike Zabrocki, Apr 25 2003

Keywords

References

  • I. G. Macdonald, Symmetric Functions and Hall Polynomials, Oxford Mathematical Monographs, Oxford Univ. Press, second edition, 1995.

Crossrefs

Cf. A008763 for Chi( [k, k], gamma)^4/ZEE(gamma) instead of Chi( [k, k], gamma)^5/ZEE(gamma) in the programs above.

Programs

  • Maple
    compsclr := proc(k) local gamma; add( combinat[Chi]( [k,k], gamma)^5/ZEE(gamma),gamma= combinat[partition](2*k)); end: ZEE := proc (mu) local res, m, i; m := 1; res := convert(mu,`*`); for i from 2 to nops(mu) do if mu[i] <> mu[i-1] then m := 1 else m := m+1 fi; res := res*m; od; res; end:

Formula

a(n) = Sum_{gamma} Chi^{(n, n)}( gamma )^5/z(gamma) the sum is over all partitions gamma of 2n Chi^lambda(gamma) is the value of the symmetric group character z(gamma) is the size of the stablizer of the conjugacy class of symmetric group indexed by the partition gamma

A060962 Expansion of (1+x^2)*(1+x^5)/( Product_{j=1..7} (1-x^j) ).

Original entry on oeis.org

1, 1, 3, 4, 7, 11, 17, 25, 36, 50, 69, 93, 125, 163, 213, 272, 346, 435, 543, 671, 825, 1005, 1218, 1466, 1756, 2090, 2478, 2921, 3430, 4009, 4669, 5414, 6259, 7207, 8274, 9468, 10803, 12289, 13944, 15777, 17809, 20052, 22528, 25249, 28243, 31522, 35115, 39041, 43327, 47995, 53078
Offset: 0

Views

Author

N. J. A. Sloane, May 05 2002

Keywords

References

  • G. E. Andrews, P. Paule and A. Riese, MacMahon's Partition Analysis VIII: Plane partition diamonds, Advances Applied Math., 27 (2001), 231-242 (Cor. 2.1, n=2).

Crossrefs

Programs

  • Magma
    R:=PowerSeriesRing(Integers(), 55); Coefficients(R!( (1+x^2)*(1+x^5)/( &*[1-x^j: j in [1..7]] ) )); // G. C. Greubel, Jan 15 2020
    
  • Maple
    seq(coeff(series((1+x^2)*(1+x^5)/(mul(1-x^j, j=1..7)), x, n+1), x, n), n = 0..55); # G. C. Greubel, Jan 15 2020
  • Mathematica
    Table[SeriesCoefficient[(1+x^2)*(1+x^5)/(1-x)/(1-x^2)/(1-x^3)/(1-x^4)/(1-x^5)/(1-x^6)/(1-x^7),{x,0,n}],{n,0,55}] (* Vaclav Kotesovec, Oct 01 2012 *)
  • PARI
    Vec((1+x^2)*(1+x^5)/(1-x)/(1-x^2)/(1-x^3)/(1-x^4)/(1-x^5)/(1-x^6)/(1-x^7) +O(x^55)) \\ Charles R Greathouse IV, Sep 27 2012
    
  • Sage
    def A060962_list(prec):
        P. = PowerSeriesRing(ZZ, prec)
        return P( (1+x^2)*(1+x^5)/(product(1-x^j for j in (1..7))) ).list()
    A060962_list(55) # G. C. Greubel, Jan 15 2020

Formula

a(n) = 1 - 263117*n/1814400 + 109537*n^2/907200 + 97*n^3/4320 + 127*n^4/72576 + n^5/14400 + n^6/907200 + 4/7*floor(n/7) + 1/3*floor(n/6) + 2/25*floor(n/5) - 11/162*floor(n/3) + (73/192 + 5*n/96)*floor(n/2) + 1/7*floor((1+n)/7) - 1/6*floor((1+n)/6) + 4/25*floor((1+n)/5) + (53/162 + n/54)*floor((1+n)/3) + 3/7*floor((2+n)/7) - 4/25*floor((2+n)/5) + 2/7*floor((3+n)/7) + 8/25*floor((3+n)/5) + 1/7*floor((4+n)/7) + 3/7*floor((5+n)/7). - Vaclav Kotesovec, Sep 29 2012

A089300 Number of planar partitions of n (A000219) that are non-squashing along rows and down columns (cf. A018819).

Original entry on oeis.org

1, 1, 3, 4, 9, 13, 25, 33, 56, 76, 122, 170, 264, 360, 538, 707, 1002, 1332, 1853, 2409, 3294
Offset: 0

Views

Author

N. J. A. Sloane, Dec 25 2003

Keywords

Examples

			E.g. a(4) = 9:
4.31.3.22.2.211.21..2..11
.....1....2.....1...1..11
....................1....
		

Crossrefs

Extensions

More terms from Wouter Meeussen, Dec 30 2003

A115375 where h[d,d] is a homogeneous symmetric function, s[d,d] is a Schur function indexed by two parts, * represents the Kronecker product and <, > is the standard scalar product on symmetric functions.

Original entry on oeis.org

1, 1, 4, 5, 12, 15, 30, 37, 65, 80, 128, 156, 234, 282, 402, 480, 657, 777, 1030, 1207, 1558, 1811, 2286, 2637, 3267, 3742, 4562, 5192, 6242, 7062, 8388, 9438, 11091, 12417, 14454, 16107, 18592, 20629, 23632, 26117, 29715, 32718, 36996, 40594
Offset: 0

Views

Author

Mike Zabrocki, Jan 21 2006

Keywords

References

  • M. W. Hero and J. F. Willenbring, Stable Hilbert series as related to the measurement of quantum entanglement, Discrete Math., 309 (2010), 6508-6514.

Crossrefs

Programs

  • PARI
    Vec((1 - x^2 + x^4) / ((1 - x)^6*(1 + x)^4*(1 + x + x^2)) + O(x^40)) \\ Colin Barker, May 10 2019

Formula

G.f.: (1 - x^2 + x^4) / ((1 - x)^6*(1 + x)^4*(1 + x + x^2)).
a(n) = a(n-1) + 4*a(n-2) - 3*a(n-3) - 7*a(n-4) + 2*a(n-5) + 8*a(n-6) + 2*a(n-7) - 7*a(n-8) - 3*a(n-9) + 4*a(n-10) + a(n-11) - a(n-12) for n>11. - Colin Barker, May 10 2019

A115376 where h[d+1,d-1] is a homogeneous symmetric function, s[d,d] is a Schur function indexed by two parts, * represents the Kronecker product and <, > is the standard scalar product on symmetric functions.

Original entry on oeis.org

1, 1, 5, 6, 16, 20, 41, 51, 90, 111, 177, 216, 321, 387, 546, 651, 882, 1041, 1366, 1597, 2042, 2367, 2962, 3407, 4187, 4782, 5787, 6567, 7842, 8847, 10443, 11718, 13692, 15288, 17703, 19677, 22603, 25018, 28532, 31458, 35644, 39158, 44108, 48294
Offset: 2

Views

Author

Mike Zabrocki, Jan 21 2006

Keywords

Crossrefs

Programs

  • Mathematica
    Drop[CoefficientList[Series[x^2/((1-x)(1-x^2)^4(1-x^3)),{x,0,50}],x],2]  (* Harvey P. Dale, Aug 24 2011 *)
  • PARI
    Vec(x^2 / ((1 - x)^6*(1 + x)^4*(1 + x + x^2)) + O(x^50)) \\ Colin Barker, May 10 2019

Formula

G.f.: x^2 / ((1 - x)^6*(1 + x)^4*(1 + x + x^2)).
a(n) = a(n-1) + 4*a(n-2) - 3*a(n-3) - 7*a(n-4) + 2*a(n-5) + 8*a(n-6) + 2*a(n-7) - 7*a(n-8) - 3*a(n-9) + 4*a(n-10) + a(n-11) - a(n-12) for n>11. - Colin Barker, May 10 2019

A251260 Expansion of (1 + 2*x + x^2 + x^3) / ((1 - x^2)^2 * (1 - x^3) * (1 - x^4)) in powers of x.

Original entry on oeis.org

1, 2, 3, 6, 8, 13, 16, 24, 28, 40, 45, 61, 68, 89, 97, 124, 134, 167, 179, 219, 233, 281, 297, 353, 372, 437, 458, 533, 557, 642, 669, 765, 795, 903, 936, 1056, 1093, 1226, 1266, 1413, 1457, 1618, 1666, 1842, 1894, 2086, 2142, 2350, 2411, 2636, 2701, 2944
Offset: 0

Views

Author

Michael Somos, Mar 20 2015

Keywords

Examples

			G.f. = 1 + 2*x + 3*x^2 + 6*x^3 + 8*x^4 + 13*x^5 + 16*x^6 + 24*x^7 + ...
		

Crossrefs

Programs

  • Magma
    m:=50; R:=PowerSeriesRing(Integers(), m); Coefficients(R!((1 + 2*x+x^2+x^3)/((1-x^2)^2*(1-x^3)*(1-x^4)))); // G. C. Greubel, Aug 03 2018
  • Mathematica
    a[ n_] := Quotient[ 5 n^3 + If[ OddQ[n], 66 n^2 + 249 n, 57 n^2 + 204 n] + 288, 288];
    a[ n_] := Length @ FindInstance[ {x > u, u > v, v > w, w >= 0, x + u == n + 6, (u + v < x + w && k == 0) || (u + v > x + w && x + u + v + w == 2 k + 1)}, {x, u, v, w, k}, Integers, 10^9];
    LinearRecurrence[{0,2,1,0,-2,-2,0,1,2,0,-1},{1,2,3,6,8,13,16,24,28,40,45},60] (* Harvey P. Dale, Jul 16 2025 *)
  • PARI
    {a(n) = (5*n^3 + if( n%2, 66*n^2 + 249*n, 57*n^2 + 204*n) + 288) \ 288};
    
  • PARI
    {a(n) = polcoeff( if( n<0, n = -8-n; -(1 + x + 2*x^2 + x^3), 1 + 2*x + x^2 + x^3) / ((1 - x^2)^2 * (1 - x^3) * (1 - x^4)) + x * O(x^n), n)};
    

Formula

a(n) = A165188(n+1) + A254708(n-1) = A254594(n-1) + A008763(n+4) for all n in Z.
0 = a(n) - 2*a(n+2) - a(n+3) + 2*a(n+5) + 2*a(n+6) - a(n+8) - 2*a(n+9) + a(n+11) for all n in Z.
a(2*n) = A254875(n) for all n in Z.
G.f.: (1 + 2*x + x^2 + x^3) / ((1 - x^2)^2 * (1 - x^3) * (1 - x^4)).
Previous Showing 11-17 of 17 results.