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The following tables describe quintright-like multiplication for a right angle divided into various numbers of parts. Squares are shaded in red, and antisquares in green. The larger tables will help the reader surmise the underlying pattern.

Omitted are any tables where the number of parts is a multiple of three, as these will contain the element 2 cos 60° which, being rational, gives multiple ways to write zero. An open question is whether anything similar can occur when the number of parts is not a multiple of three.

5-part
Multiplication

(quintrights)
Q
2 cos (90° / 5)
2 sin (360° / 5)
1.902113
R
2 cos (180° / 5)
2 sin (270° / 5)
1.618034
S
2 cos (270° / 5)
2 sin (180° / 5)
1.175571
T
2 cos (360° / 5)
2 sin (90° / 5)
0.618034
Q
1.902113
2 + R
3.618034
Q + S
3.077684
R + T
2.236068
S
1.175571
R
1.618034
Q + S
3.077684
2 + T
2.618034
Q
1.902113
R − T
1.000000
S
1.175571
R + T
2.236068
Q
1.902113
2 − T
1.381966
Q − S
0.726543
T
0.618034
S
1.175571
R − T
1.000000
Q − S
0.726543
2 − R
0.381966
  R − T = RT = 1
QS = √5

7-part
Multiplication

(septrights)
Q
2 cos (90° / 7)
2 sin (540° / 7)
1.949856
R
2 cos (180° / 7)
2 sin (450° / 7)
1.801938
S
2 cos (270° / 7)
2 sin (360° / 7)
1.563663
T
2 cos (360° / 7)
2 sin (270° / 7)
1.246980
U
2 cos (450° / 7)
2 sin (180° / 7)
0.867767
V
2 cos (540° / 7)
2 sin (90° / 7)
0.445042
Q
1.949856
2 + R
3.801938
Q + S
3.513519
R + T
3.048917
S + U
2.431430
T + V
1.692021
U
0.867767
R
1.801938
Q + S
3.513519
2 + T
3.246980
Q + U
2.817623
R + V
2.246980
S
1.563663
T − V
0.801938
S
1.563663
R + T
3.048917
Q + U
2.817623
2 + V
2.445042
Q
1.949856
R − V
1.356896
S − U
0.695895
T
1.246980
S + U
2.431430
R + V
2.246980
Q
1.949856
2 − V
1.554958
Q − U
1.082088
R − T
0.554958
U
0.867767
T + V
1.692021
S
1.563663
R − V
1.356896
Q − U
1.082088
2 − T
0.753020
Q − S
0.386193
V
0.445042
U
0.867767
T − V
0.801938
S − U
0.695895
R − T
0.554958
Q − S
0.386193
2 − R
0.198062
  R − T + V = RTV = 1
QSU = √7
Many identities can be found on a page devoted to septrights.

11-part
Multiplication
Q
2 cos (90° / 11)
2 sin (900° / 11)
1.979643
R
2 cos (180° / 11)
2 sin (810° / 11)
1.918986
S
2 cos (270° / 11)
2 sin (720° / 11)
1.819264
T
2 cos (360° / 11)
2 sin (630° / 11)
1.682507
U
2 cos (450° / 11)
2 sin (540° / 11)
1.511499
V
2 cos (540° / 11)
2 sin (450° / 11)
1.309721
W
2 cos (630° / 11)
2 sin (360° / 11)
1.081282
X
2 cos (720° / 11)
2 sin (270° / 11)
0.830830
Y
2 cos (810° / 11)
2 sin (180° / 11)
0.563465
Z
2 cos (900° / 11)
2 sin (90° / 11)
0.284630
Q
1.979643
2 + R
3.918986
Q + S
3.798907
R + T
3.601493
S + U
3.330763
T + V
2.992229
U + W
2.592781
V + X
2.140551
W + Y
1.644747
X + Z
1.115460
Y
0.563465
R
1.918986
Q + S
3.798907
2 + T
3.682507
Q + U
3.491142
R + V
3.228707
S + W
2.900546
T + X
2.513337
U + Y
2.074964
V + Z
1.594351
W
1.081282
X − Z
0.546200
S
1.819264
R + T
3.601493
Q + U
3.491142
2 + V
3.309721
Q + W
3.060925
R + X
2.749816
S + Y
2.382729
T + Z
1.967137
U
1.511499
V − Z
1.025092
W − Y
0.517817
T
1.682507
S + U
3.330763
R + V
3.228707
Q + W
3.060925
2 + X
2.830830
Q + Y
2.543108
R + Z
2.203616
S
1.819264
T − Z
1.397877
U − Y
0.948034
V − X
0.478891
U
1.511499
T + V
2.992229
S + W
2.900546
R + X
2.749816
Q + Y
2.543108
2 + Z
2.284630
Q
1.979643
R − Z
1.634356
S − Y
1.255799
T − X
0.851677
U − W
0.430218
V
1.309721
U + W
2.592781
T + X
2.513337
S + Y
2.382729
R + Z
2.203616
Q
1.979643
2 − Z
1.715370
Q − Y
1.416178
R − X
1.088156
S − W
0.737982
T − V
0.372786
W
1.081282
V + X
2.140551
U + Y
2.074964
T + Z
1.967137
S
1.819264
R − Z
1.634356
Q − Y
1.416178
2 − X
1.169170
Q − W
0.898361
R − V
0.609264
S − U
0.307765
X
0.830830
W + Y
1.644747
V + Z
1.594351
U
1.511499
T − Z
1.397877
S − Y
1.255799
R − X
1.088156
Q − W
0.898361
2 − V
0.690279
Q − U
0.468144
R − T
0.236479
Y
0.563465
X + Z
1.115460
W
1.081282
V − Z
1.025092
U − Y
0.948034
T − X
0.851677
S − W
0.737982
R − V
0.609264
Q − U
0.468144
2 − T
0.317493
Q − S
0.160379
Z
0.284630
Y
0.563465
X − Z
0.546200
W − Y
0.517817
V − X
0.478891
U − W
0.430218
T − V
0.372786
S − U
0.307765
R − T
0.236479
Q − S
0.160379
2 − R
0.081014
  R − T + V − X + Z = RTVXZ = 1
QSUWY = √11

13-part
Multiplication
Q
2 cos (90° / 13)
2 sin (1080° / 13)
1.985418
R
2 cos (180° / 13)
2 sin (990° / 13)
1.941884
S
2 cos (270° / 13)
2 sin (900° / 13)
1.870032
T
2 cos (360° / 13)
2 sin (810° / 13)
1.770912
U
2 cos (450° / 13)
2 sin (720° / 13)
1.645968
V
2 cos (540° / 13)
2 sin (630° / 13)
1.497021
W
2 cos (630° / 13)
2 sin (540° / 13)
1.326245
X
2 cos (720° / 13)
2 sin (450° / 13)
1.136129
Y
2 cos (810° / 13)
2 sin (360° / 13)
0.929446
Z
2 cos (900° / 13)
2 sin (270° / 13)
0.709210
A
2 cos (990° / 13)
2 sin (180° / 13)
0.478631
B
2 cos (1080° / 13)
2 sin (90° / 13)
0.241073
Q
1.985418
2 + R
3.941884
Q + S
3.855450
R + T
3.712796
S + U
3.516000
T + V
3.267934
U + W
2.972213
V + X
2.633151
W + Y
2.255692
X + Z
1.845339
Y + A
1.408078
Z + B
0.950283
A
0.478631
R
1.941884
Q + S
3.855450
2 + T
3.770912
Q + U
3.631385
R + V
3.438905
S + W
3.196278
T + X
2.907042
U + Y
2.575414
V + Z
2.206231
W + A
1.804877
X + B
1.377203
Y
0.929446
Z − B
0.468136
S
1.870032
R + T
3.712796
Q + U
3.631385
2 + V
3.497021
Q + W
3.311663
R + X
3.078013
S + Y
2.799479
T + Z
2.480122
U + A
2.124599
V + B
1.738095
W
1.326245
X − B
0.895056
Y − A
0.450815
T
1.770912
S + U
3.516000
R + V
3.438905
Q + W
3.311663
2 + X
3.136129
Q + Y
2.914864
R + Z
2.651093
S + A
2.348664
T + B
2.011985
U
1.645968
V − B
1.255948
W − A
0.847614
X − Z
0.426920
U
1.645968
T + V
3.267934
S + W
3.196278
R + X
3.078013
Q + Y
2.914864
2 + Z
2.709210
Q + A
2.464049
R + B
2.182957
S
1.870032
T − B
1.529839
U − A
1.167336
V − Z
0.787812
W − Y
0.396799
V
1.497021
U + W
2.972213
T + X
2.907042
S + Y
2.799479
R + Z
2.651093
Q + A
2.464049
2 + B
2.241073
Q
1.985418
R − B
1.700810
S − A
1.391401
T − Z
1.061702
U − Y
0.716521
V − X
0.360892
W
1.326245
V + X
2.633151
U + Y
2.575414
T + Z
2.480122
S + A
2.348664
R + B
2.182957
Q
1.985418
2 − B
1.758927
Q − A
1.506786
R − Z
1.232674
S − Y
0.940586
T − X
0.634783
U − W
0.319722
X
1.136129
W + Y
2.255692
V + Z
2.206231
U + A
2.124599
T + B
2.011985
S
1.870032
R − B
1.700810
Q − A
1.506786
2 − Z
1.290790
Q − Y
1.055971
R − X
0.805754
S − W
0.543787
T − V
0.273891
Y
0.929446
X + Z
1.845339
W + A
1.804877
V + B
1.738095
U
1.645968
T − B
1.529839
S − A
1.391401
R − Z
1.232674
Q − Y
1.055971
2 − X
0.863871
Q − W
0.659172
R − V
0.444862
S − U
0.224065
Z
0.709210
Y + A
1.408078
X + B
1.377203
W
1.326245
V − B
1.255948
U − A
1.167336
T − Z
1.061702
S − Y
0.940586
R − X
0.805754
Q − W
0.659172
2 − V
0.502979
Q − U
0.339450
R − T
0.170972
A
0.478631
Z + B
0.950283
Y
0.929446
X − B
0.895056
W − A
0.847614
V − Z
0.787812
U − Y
0.716521
T − X
0.634783
S − W
0.543787
R − V
0.444862
Q − U
0.339450
2 − T
0.229088
Q − S
0.115385
B
0.241073
A
0.478631
Z − B
0.468136
Y − A
0.450815
X − Z
0.426920
W − Y
0.396799
V − X
0.360892
U − W
0.319722
T − V
0.273891
S − U
0.224065
R − T
0.170972
Q − S
0.115385
2 − R
0.058116
  R − T + V − X + Z − B = RTVXZB = 1
QSUWYA = √13


Multiplication can be extended to systems having a number of parts that is twice an odd number.

Equivalences of some constants

In the
10- and 14-part
tables
In the
5- and 7-part
tables
RQ
TR
VS
XT
ZU
BV

10-part
Multiplication
Q
2 cos (90° / 10)
2 sin (810° / 10)
1.975377
R
2 cos (180° / 10)
2 sin (720° / 10)
1.902113
S
2 cos (270° / 10)
2 sin (630° / 10)
1.782013
T
2 cos (360° / 10)
2 sin (540° / 10)
1.618034
U
2 cos (450° / 10)
2 sin (450° / 10)
1.414214
V
2 cos (540° / 10)
2 sin (360° / 10)
1.175571
W
2 cos (630° / 10)
2 sin (270° / 10)
0.907981
X
2 cos (720° / 10)
2 sin (180° / 10)
0.618034
Y
2 cos (810° / 10)
2 sin (90° / 10)
0.312869
Q
1.975377
2 + R
3.902113
Q + S
3.757390
R + T
3.520147
S + U
3.196227
T + V
2.793604
U + W
2.322195
V + X
1.793604
W + Y
1.220850
X
0.618034
R
1.902113
Q + S
3.757390
2 + T
3.618034
Q + U
3.389590
R + V
3.077684
S + W
2.689994
T + X
2.236068
U + Y
1.727082
V
1.175571
W − Y
0.595112
S
1.782013
R + T
3.520147
Q + U
3.389590
2 + V
3.175571
Q + W
2.883358
R + X
2.520147
S + Y
2.094882
T
1.618034
U − Y
1.101345
V − X
0.557537
T
1.618034
S + U
3.196227
R + V
3.077684
Q + W
2.883358
2 + X
2.618034
Q + Y
2.288246
R
1.902113
S − Y
1.469144
T − X
1.000000
U − W
0.506233
U
1.414214
T + V
2.793604
S + W
2.689994
R + X
2.520147
Q + Y
2.288246
2
2.000000
Q − Y
1.662508
R − X
1.284079
S − W
0.874032
T − V
0.442463
V
1.175571
U + W
2.322195
T + X
2.236068
S + Y
2.094882
R
1.902113
Q − Y
1.662508
2 − X
1.381966
Q − W
1.067396
R − V
0.726543
S − U
0.367799
W
0.907981
V + X
1.793604
U + Y
1.727082
T
1.618034
S − Y
1.469144
R − X
1.284079
Q − W
1.067396
2 − V
0.824429
Q − U
0.561163
R − T
0.284079
X
0.618034
W + Y
1.220850
V
1.175571
U − Y
1.101345
T − X
1.000000
S − W
0.874032
R − V
0.726543
Q − U
0.561163
2 − T
0.381966
Q − S
0.193364
Y
0.312869
X
0.618034
W − Y
0.595112
V − X
0.557537
U − W
0.506233
T − V
0.442463
S − U
0.367799
R − T
0.284079
Q − S
0.193364
2 − R
0.097887
  T − X = TX = 1
RV = √5

14-part
Multiplication
Q
2 cos (90° / 14)
2 sin (1170° / 14)
1.987424
R
2 cos (180° / 14)
2 sin (1080° / 14)
1.949856
S
2 cos (270° / 14)
2 sin (990° / 14)
1.887767
T
2 cos (360° / 14)
2 sin (900° / 14)
1.801938
U
2 cos (450° / 14)
2 sin (810° / 14)
1.693448
V
2 cos (540° / 14)
2 sin (720° / 14)
1.563663
W
2 cos (630° / 14)
2 sin (630° / 14)
1.414214
X
2 cos (720° / 14)
2 sin (540° / 14)
1.246980
Y
2 cos (810° / 14)
2 sin (450° / 14)
1.064064
Z
2 cos (900° / 14)
2 sin (360° / 14)
0.867767
A
2 cos (990° / 14)
2 sin (270° / 14)
0.660558
B
2 cos (1080° / 14)
2 sin (180° / 14)
0.445042
C
2 cos (1170° / 14)
2 sin (90° / 14)
0.223929
Q
1.987424
2 + R
3.949856
Q + S
3.875191
R + T
3.751794
S + U
3.581215
T + V
3.365601
U + W
3.107662
V + X
2.810643
W + Y
2.478278
X + Z
2.114747
Y + A
1.724622
Z + B
1.312809
A + C
0.884487
B
0.445042
R
1.949856
Q + S
3.875191
2 + T
3.801938
Q + U
3.680873
R + V
3.513519
S + W
3.301980
T + X
3.048917
U + Y
2.757513
V + Z
2.431430
W + A
2.074772
X + B
1.692021
Y + C
1.287993
Z
0.867767
A − C
0.436629
S
1.887767
R + T
3.751794
Q + U
3.680873
2 + V
3.563663
Q + W
3.401638
R + X
3.196835
S + Y
2.951831
T + Z
2.669705
U + A
2.354007
V + B
2.008705
W + C
1.638143
X
1.246980
Y − C
0.840135
Z − B
0.422726
T
1.801938
S + U
3.581215
R + V
3.513519
Q + W
3.401638
2 + X
3.246980
Q + Y
3.051489
R + Z
2.817623
S + A
2.548325
T + B
2.246980
U + C
1.917377
V
1.563663
W − C
1.190285
X − B
0.801938
Y − A
0.403506
U
1.693448
T + V
3.365601
S + W
3.301980
R + X
3.196835
Q + Y
3.051489
2 + Z
2.867767
Q + A
2.647983
R + B
2.394898
S + C
2.111696
T
1.801938
U − C
1.469519
V − B
1.118621
W − A
0.753655
X − Z
0.379212
V
1.563663
U + W
3.107662
T + X
3.048917
S + Y
2.951831
R + Z
2.817623
Q + A
2.647983
2 + B
2.445042
Q + C
2.211353
R
1.949856
S − C
1.663838
T − B
1.356896
U − A
1.032890
V − Z
0.695895
W − Y
0.350149
W
1.414214
V + X
2.810643
U + Y
2.757513
T + Z
2.669705
S + A
2.548325
R + B
2.394898
Q + C
2.211353
2
2.000000
Q − C
1.763495
R − B
1.504814
S − A
1.227209
T − Z
0.934170
U − Y
0.629384
V − X
0.316683
X
1.246980
W + Y
2.478278
V + Z
2.431430
U + A
2.354007
T + B
2.246980
S + C
2.111696
R
1.949856
Q − C
1.763495
2 − B
1.554958
Q − A
1.326866
R − Z
1.082088
S − Y
0.823703
T − X
0.554958
U − W
0.279235
Y
1.064064
X + Z
2.114747
W + A
2.074772
V + B
2.008705
U + C
1.917377
T
1.801938
S − C
1.663838
R − B
1.504814
Q − A
1.326866
2 − Z
1.132233
Q − Y
0.923360
R − X
0.702876
S − W
0.473553
T − V
0.238275
Z
0.867767
Y + A
1.724622
X + B
1.692021
W + C
1.638143
V
1.563663
U − C
1.469519
T − B
1.356896
S − A
1.227209
R − Z
1.082088
Q − Y
0.923360
2 − X
0.753020
Q − W
0.573211
R − V
0.386193
S − U
0.194318
A
0.660558
Z + B
1.312809
Y + C
1.287993
X
1.246980
W − C
1.190285
V − B
1.118621
U − A
1.032890
T − Z
0.934170
S − Y
0.823703
R − X
0.702876
Q − W
0.573211
2 − V
0.436337
Q − U
0.293976
R − T
0.147918
B
0.445042
A + C
0.884487
Z
0.867767
Y − C
0.840135
X − B
0.801938
W − A
0.753655
V − Z
0.695895
U − Y
0.629384
T − X
0.554958
S − W
0.473553
R − V
0.386193
Q − U
0.293976
2 − T
0.198062
Q − S
0.099658
C
0.223929
B
0.445042
A − C
0.436629
Z − B
0.422726
Y − A
0.403506
X − Z
0.379212
W − Y
0.350149
V − X
0.316683
U − W
0.279235
T − V
0.238275
S − U
0.194318
R − T
0.147918
Q − S
0.099658
2 − R
0.050144
  T − X + B = TXB = 1
RVZ = √7