From 69064893c437aaf7ee206839115a51caea9f37eb Mon Sep 17 00:00:00 2001 From: Andrew Tonks <48631703+0-andy-0@users.noreply.github.com> Date: Mon, 15 Jul 2024 11:58:11 +0200 Subject: [PATCH 1/2] Update ncsf.py Correction lines 184-189: Psi is not the tensor algebra on the primitives but on the generators of this free Lie algebra. --- src/sage/combinat/ncsf_qsym/ncsf.py | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/src/sage/combinat/ncsf_qsym/ncsf.py b/src/sage/combinat/ncsf_qsym/ncsf.py index 65b03741885..731aa742ece 100644 --- a/src/sage/combinat/ncsf_qsym/ncsf.py +++ b/src/sage/combinat/ncsf_qsym/ncsf.py @@ -182,8 +182,11 @@ class NonCommutativeSymmetricFunctions(UniqueRepresentation, Parent): bialgebra structure, which cooperates with the grading to form a connected graded bialgebra. Thus, as any connected graded bialgebra, ``Psi`` is a Hopf algebra. Over ``QQ`` (or any other `\QQ`-algebra), - this Hopf algebra ``Psi`` is isomorphic to the tensor algebra of - its space of primitive elements. + this Hopf algebra ``Psi`` is isomorphic to the universal enveloping + algebra of its space of primitive elements. Here, the primitives + form a countably generated free Lie algebra, so ``Psi`` is isomorphic + to the tensor algebra on a countably infinite dimensional vector + space. The antipode is an anti-algebra morphism; in the ``Psi`` basis, it sends the generators to their opposites and changes their sign if From fc78fd0f92e32c1798865a57688ee480b5299383 Mon Sep 17 00:00:00 2001 From: Andrew Tonks <48631703+0-andy-0@users.noreply.github.com> Date: Mon, 15 Jul 2024 14:52:29 +0200 Subject: [PATCH 2/2] Update ncsf.py trailing whitespace removed --- src/sage/combinat/ncsf_qsym/ncsf.py | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/src/sage/combinat/ncsf_qsym/ncsf.py b/src/sage/combinat/ncsf_qsym/ncsf.py index 731aa742ece..dbab31a0080 100644 --- a/src/sage/combinat/ncsf_qsym/ncsf.py +++ b/src/sage/combinat/ncsf_qsym/ncsf.py @@ -182,10 +182,10 @@ class NonCommutativeSymmetricFunctions(UniqueRepresentation, Parent): bialgebra structure, which cooperates with the grading to form a connected graded bialgebra. Thus, as any connected graded bialgebra, ``Psi`` is a Hopf algebra. Over ``QQ`` (or any other `\QQ`-algebra), - this Hopf algebra ``Psi`` is isomorphic to the universal enveloping - algebra of its space of primitive elements. Here, the primitives - form a countably generated free Lie algebra, so ``Psi`` is isomorphic - to the tensor algebra on a countably infinite dimensional vector + this Hopf algebra ``Psi`` is isomorphic to the universal enveloping + algebra of its space of primitive elements. Here, the primitives + form a countably generated free Lie algebra, so ``Psi`` is isomorphic + to the tensor algebra on a countably infinite dimensional vector space. The antipode is an anti-algebra morphism; in the ``Psi`` basis, it