f*Σ_{sym}((a-b)^2)/24 =

取等有 (1,1,1,1), (-1,-1,0,0), (-1,-1,1,1), (1,1,1,-1/3) 等
——求和都是24项——
1/1296s((-81a^4+36a^3b+36a^3c+36a^3d+22a^2b^2-16a^2bc-16a^2bd+22a^2c^2-16a^2cd+22a^2d^2-68ab^3+28ab^2c+28ab^2d+28abc^2+28abd^2-68ac^3+28ac^2d+28acd^2-68ad^3+27b^4+16b^3c+16b^3d-22b^2c^2-40b^2cd-22b^2d^2+16bc^3-40bc^2d-40bcd^2+16bd^3+27c^4+16c^3d-22c^2d^2+16cd^3+27d^4)^2)+1/7128s((-126a^4+37a^3b+37a^3c+94a^3d+19a^2b^2-122a^2bc+45a^2bd+19a^2c^2+45a^2cd+22a^2d^2-81ab^3+61ab^2c+80ab^2d+61abc^2+11abd^2-81ac^3+80ac^2d+11acd^2-198ad^3+63b^4+44b^3c-47b^3d-38b^2c^2-125b^2cd-11b^2d^2+44bc^3-125bc^2d-22bcd^2+99bd^3+63c^4-47c^3d-11c^2d^2+99cd^3)^2)+1/21384s((a-b)^2(-189a^3-71a^2b+141a^2c-7a^2d-71ab^2+106abc-190abd+33ac^2+170acd+57ad^2-189b^3+141b^2c-7b^2d+33bc^2+170bcd+57bd^2-297c^3+33c^2d+205cd^2-125d^3)^2)+1/60588s((-234a^4+86a^3b+86a^3c+140a^3d+15a^2b^2-176a^2bd+15a^2c^2-176a^2cd+374a^2d^2-188ab^3+192ab^2c-18ab^2d+192abc^2-38abd^2-188ac^3-18ac^2d-38acd^2+117b^4+6b^3c+26b^3d-222b^2c^2+98b^2cd-91b^2d^2+6bc^3+98bc^2d-116bcd^2+117c^4+26c^3d-91c^2d^2)^2)+1/5189907492s((-76275a^4+75434a^3b+79120a^3c-52854a^3d-10368a^2b^2+68160a^2bc-25798a^2bd-14871a^2c^2-23594a^2cd+23421a^2d^2-127274ab^3-3648ab^2c+40774ab^2d+70272abd^2-128794ac^3+45980ac^2d+68790acd^2+34803b^4+37232b^3c+43638b^3d-7017b^2c^2-36310b^2cd+8835b^2d^2+32026bc^3-33308bc^2d-171318bcd^2+41472c^4+41472c^3d)^2)+4/2590137s((-378a^4+617a^3b+265a^3c-378a^3d+720a^2b^2-732a^2bc-349a^2bd+120a^2c^2+325a^2cd-221ab^3-1068ab^2c-83ab^2d-252abc^2-199ac^3+629ac^2d+1026acd^2+54b^4+95b^3c+54b^3d+186b^2c^2+233b^2cd+469bc^3+271bc^2d+324c^4-702c^3d-1026c^2d^2)^2)+4/8221958217s((-32202a^4+25953a^3b+21825a^3c-4842a^3d+39920a^2b^2-38908a^2bc-28981a^2bd+4280a^2c^2+3485a^2cd+27360a^2d^2-16309ab^3-38092ab^2c-11387ab^2d+3812abc^2-19471ac^3+30541ac^2d+36594acd^2+1926b^4+11815b^3c+1926b^3d-7606b^2c^2+16737b^2cd+12781bc^3+26199bc^2d+30276c^4-33678c^3d-63954c^2d^2)^2)+8/22024727739s((-49545a^4+19348a^3b+74810a^3c-28098a^3d-11556a^2b^2+53040a^2bc-7496a^2bd-14067a^2c^2-30358a^2cd+21447a^2d^2-77128ab^3+18864ab^2c+24188ab^2d+78324abd^2-92198ac^3+25930ac^2d+3321b^4+54874b^3c+17826b^3d-10329b^2c^2-36410b^2cd+14505b^2d^2-15658bc^3-11806bc^2d-114276bcd^2+46224c^4+46224c^3d)^2)+10/4233s((a-b)^2(9a^3-a^2b-11a^2c+9a^2d-ab^2-18abc+22abd-20ac^2+12acd+9b^3-11b^2c+9b^2d-20bc^2+12bcd)^2)+10/214981371s((a-b)^2(27a^3-5647a^2b+5611a^2c+27a^2d-5647ab^2+5590abc-5578abd-60ac^2+5680acd+27b^3+5611b^2c+27b^2d-60bc^2+5680bcd-5644c^3-5644c^2d)^2)+40/50787s((-18a^4+21a^3b+21a^3c-18a^3d+20a^2b^2+14a^2bc-25a^2bd+20a^2c^2-25a^2cd-10ab^3-7ab^2c+13ab^2d-7abc^2-10ac^3+13ac^2d+9b^4-11b^3c+9b^3d-40b^2c^2+12b^2cd-11bc^3+12bc^2d+9c^4+9c^3d)^2)

取等有 (1,1,1,1), (-1,-1,0,0), (-1,-1,1,1), (1,1,1,-1/3) 等
——求和都是24项——
1/1296s((-81a^4+36a^3b+36a^3c+36a^3d+22a^2b^2-16a^2bc-16a^2bd+22a^2c^2-16a^2cd+22a^2d^2-68ab^3+28ab^2c+28ab^2d+28abc^2+28abd^2-68ac^3+28ac^2d+28acd^2-68ad^3+27b^4+16b^3c+16b^3d-22b^2c^2-40b^2cd-22b^2d^2+16bc^3-40bc^2d-40bcd^2+16bd^3+27c^4+16c^3d-22c^2d^2+16cd^3+27d^4)^2)+1/7128s((-126a^4+37a^3b+37a^3c+94a^3d+19a^2b^2-122a^2bc+45a^2bd+19a^2c^2+45a^2cd+22a^2d^2-81ab^3+61ab^2c+80ab^2d+61abc^2+11abd^2-81ac^3+80ac^2d+11acd^2-198ad^3+63b^4+44b^3c-47b^3d-38b^2c^2-125b^2cd-11b^2d^2+44bc^3-125bc^2d-22bcd^2+99bd^3+63c^4-47c^3d-11c^2d^2+99cd^3)^2)+1/21384s((a-b)^2(-189a^3-71a^2b+141a^2c-7a^2d-71ab^2+106abc-190abd+33ac^2+170acd+57ad^2-189b^3+141b^2c-7b^2d+33bc^2+170bcd+57bd^2-297c^3+33c^2d+205cd^2-125d^3)^2)+1/60588s((-234a^4+86a^3b+86a^3c+140a^3d+15a^2b^2-176a^2bd+15a^2c^2-176a^2cd+374a^2d^2-188ab^3+192ab^2c-18ab^2d+192abc^2-38abd^2-188ac^3-18ac^2d-38acd^2+117b^4+6b^3c+26b^3d-222b^2c^2+98b^2cd-91b^2d^2+6bc^3+98bc^2d-116bcd^2+117c^4+26c^3d-91c^2d^2)^2)+1/5189907492s((-76275a^4+75434a^3b+79120a^3c-52854a^3d-10368a^2b^2+68160a^2bc-25798a^2bd-14871a^2c^2-23594a^2cd+23421a^2d^2-127274ab^3-3648ab^2c+40774ab^2d+70272abd^2-128794ac^3+45980ac^2d+68790acd^2+34803b^4+37232b^3c+43638b^3d-7017b^2c^2-36310b^2cd+8835b^2d^2+32026bc^3-33308bc^2d-171318bcd^2+41472c^4+41472c^3d)^2)+4/2590137s((-378a^4+617a^3b+265a^3c-378a^3d+720a^2b^2-732a^2bc-349a^2bd+120a^2c^2+325a^2cd-221ab^3-1068ab^2c-83ab^2d-252abc^2-199ac^3+629ac^2d+1026acd^2+54b^4+95b^3c+54b^3d+186b^2c^2+233b^2cd+469bc^3+271bc^2d+324c^4-702c^3d-1026c^2d^2)^2)+4/8221958217s((-32202a^4+25953a^3b+21825a^3c-4842a^3d+39920a^2b^2-38908a^2bc-28981a^2bd+4280a^2c^2+3485a^2cd+27360a^2d^2-16309ab^3-38092ab^2c-11387ab^2d+3812abc^2-19471ac^3+30541ac^2d+36594acd^2+1926b^4+11815b^3c+1926b^3d-7606b^2c^2+16737b^2cd+12781bc^3+26199bc^2d+30276c^4-33678c^3d-63954c^2d^2)^2)+8/22024727739s((-49545a^4+19348a^3b+74810a^3c-28098a^3d-11556a^2b^2+53040a^2bc-7496a^2bd-14067a^2c^2-30358a^2cd+21447a^2d^2-77128ab^3+18864ab^2c+24188ab^2d+78324abd^2-92198ac^3+25930ac^2d+3321b^4+54874b^3c+17826b^3d-10329b^2c^2-36410b^2cd+14505b^2d^2-15658bc^3-11806bc^2d-114276bcd^2+46224c^4+46224c^3d)^2)+10/4233s((a-b)^2(9a^3-a^2b-11a^2c+9a^2d-ab^2-18abc+22abd-20ac^2+12acd+9b^3-11b^2c+9b^2d-20bc^2+12bcd)^2)+10/214981371s((a-b)^2(27a^3-5647a^2b+5611a^2c+27a^2d-5647ab^2+5590abc-5578abd-60ac^2+5680acd+27b^3+5611b^2c+27b^2d-60bc^2+5680bcd-5644c^3-5644c^2d)^2)+40/50787s((-18a^4+21a^3b+21a^3c-18a^3d+20a^2b^2+14a^2bc-25a^2bd+20a^2c^2-25a^2cd-10ab^3-7ab^2c+13ab^2d-7abc^2-10ac^3+13ac^2d+9b^4-11b^3c+9b^3d-40b^2c^2+12b^2cd-11bc^3+12bc^2d+9c^4+9c^3d)^2)