For n≡0,1(mod4), let An be the alternating subgroup of Sn, and define
TSAn+(s,t)=π∈An∑tdes(π)+1sides(π)+1,TSAn−(s,t)=π∈Sn∖An∑tdes(π)+1sides(π)+1.
For even n, define the type-B polynomials TSBn+(s,t) and TSBn−(s,t) by summing tdesB(π)sidesB(π) over Bn+ and Bn−. For positive n, define the type-D polynomials TSDn+(s,t) and TSDn−(s,t) analogously over Dn+ and Dn−. Gamma-positivity conjectures. (1) If n≡0,1(mod4), then
TSAn±(s,t)=i,j∑γn,i,j±(st)i(s+t)j(1+st)n+1−2i−j,γn,i,j±≥0.
(2) If n≡0(mod2), then
TSBn±(s,t)=i,j∑γn,i,jB,±(st)i(s+t)j(1+st)n−2i−j,γn,i,jB,±≥0.
(3) For every positive integer n,
TSDn±(s,t)=i,j∑γn,i,jD,±(st)i(s+t)j(1+st)n−2i−j,γn,i,jD,±≥0.
These conjectures extend gamma positivity from the two-sided Eulerian polynomial to positive and negative elements in types A, B, and D. The supplied text gives no resolution status for them.