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 1-2 of 2 results.

A129548 Measures of entanglement in 3-qbits.

Original entry on oeis.org

1, 1, 8, 9, 36, 43, 120, 147, 329, 406, 784, 966, 1680, 2058, 3312, 4026, 6105, 7359, 10648, 12727, 17732, 21021, 28392, 33397, 43953, 51324, 66080, 76636, 96832, 111588, 138720, 158916, 194769, 221901, 268584, 304437, 364420, 411103, 487256, 547239, 642873
Offset: 0

Views

Author

Mike Zabrocki, Apr 20 2007

Keywords

References

  • David Meyer and Nolan Wallach, Invariants for multiple qubits: the case of 3 qubits, Mathematics of quantum computing, Computational Mathematics Series, 77-98, Chapman & Hall/CRC Press, 2002.

Crossrefs

Programs

  • Magma
    [(2*n+3+(-1)^n)*(2*n+7+(-1)^n)*(2*n+11+(-1)^n)*(2*n^3+27*n^2+169*n+387-3*(n^2-5*n-31)*(-1)^n)/184320 : n in [0..50]]; // Wesley Ivan Hurt, Oct 15 2015
  • Maple
    A129548:=n->(2*n+3+(-1)^n)*(2*n+7+(-1)^n)*(2*n+11+(-1)^n)*(2*n^3+27*n^2+169*n+387-3*(n^2-5*n-31)*(-1)^n)/184320: seq(A129548(n), n=0..50); # Wesley Ivan Hurt, Oct 15 2015
  • Mathematica
    CoefficientList[Series[(x^2 - x + 1)*(x^2 + 1)/((1 - x)^7*(x + 1)^5), {x, 0, 50}], x] (* Wesley Ivan Hurt, Oct 15 2015 *)
  • PARI
    Vec(-(x^2-x+1)*(x^2+1)/((x-1)^7*(x+1)^5) + O(x^50)) \\ Colin Barker, Oct 15 2015
    

Formula

a(n) = [x^(2n)] (1+x^4)*(1+x^4+x^8)/((1-x^2)*(1-x^4)^5*(1-x^6)).
a(n) = (2*n+3+(-1)^n)*(2*n+7+(-1)^n)*(2*n+11+(-1)^n)*(2*n^3+27*n^2+169*n+387-3*(n^2-5*n-31)*(-1)^n)/184320. - Luce ETIENNE, Oct 15 2015.
From Colin Barker, Oct 15 2015: (Start)
a(n) = (n^6+24*n^5+280*n^4+1920*n^3+7504*n^2+14976*n+11520)/11520 (n even).
a(n) = (n^6+24*n^5+235*n^4+1200*n^3+3319*n^2+4536*n+2205)/11520 (n odd).
G.f.: -(x^2-x+1)*(x^2+1) / ((x-1)^7*(x+1)^5). (End)
a(n) = 2*a(n-1)+4*(n-2)-10*a(n-3)-5*a(n-4)+20*a(n-5)-20*a(n-7)+5*a(n-8)+10*a(n-9)-4*a(n-10)-2*a(n-11)+a(n-12) for n>11. - Wesley Ivan Hurt, Oct 15 2015

A129550 Number of real polynomial invariants for the action of 4 copies of U(2) on the fourth tensor power of C^2.

Original entry on oeis.org

1, 1, 8, 20, 98, 293, 1128, 3409, 10846, 30480, 84652, 217677, 544312, 1289225, 2961626, 6528284, 13980717, 28963980, 58464510, 114806429, 220298632, 412950779, 758418342, 1365044296, 2412766496, 4189995629, 7159916414
Offset: 0

Views

Author

Mike Zabrocki, Apr 20 2007

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.
  • Nolan R. Wallach, The Hilbert series for measures of entanglement in 4 qubits, Acta Appl. Math. 86(2005),203-220.

Crossrefs

Formula

G.f.: (R(q) + q^76*R(1/q))/((1 - q^2)*(1 - q^4)^7*(1 - q^6)^6*(1 - q^8)^4*(1 - q^10)) where R(q) = 1 + 6*q^6 + 46*q^8 + 110*q^10 + 344*q^12 + 844*q^14 + 2154*q^16 + 4606*q^18 + 9397*q^20 + 16848*q^22 + 28747*q^24 + 44580*q^26 + 65366*q^28 + 88036*q^30 + 111909*q^32 + 131368*q^34 + 145676*q^36 + 149860/2*q^38.
Showing 1-2 of 2 results.