Euler totient ratio φ(n)/n --- the fraction of integers below n that are coprime to n, dense in (0,1) with a fractal structure governed by prime factorization
Standard analysis sees: anti-correlated (alternating); anti-persistent; blue spectrum (high-frequency power); strongly periodic; monofractal; stationary. The atlas finds no named structure, but the source is distinctively extreme on Heisenberg (Nil) (centered):area_length_ratio (+4.8z) — beyond what the standard bank predicts for it. It sits beside Logistic r=3.65 (Banded Chaos) in the atlas (standard-bank rank 21) — a neighbor conventional features miss.
Heisenberg (Nil) (centered):area_length_ratio | +4.8z | bank-miss 1.9σ |
Heisenberg (Nil) (centered):xy_spread | +4.7z | bank-miss 2.2σ |
Gottwald-Melbourne:k_variance | +4.1z | bank-miss 1.7σ |
Bispectrum:off_diagonal_ratio | -3.3z | bank-miss 1.3σ |
Projective ℙ²:cross_ratio_std | +2.9z | bank-miss 1.2σ |
S² × ℝ (Thurston):great_circle_dispersion | +2.4z | bank-miss 1.4σ |
Möbius-S³:spinorial_asymmetry | +2.2z | bank-miss 3.3σ |









_(centered)/signed_log_z/Euler_Totient_Ratio.png)
_(centered)/xy_path/Euler_Totient_Ratio.png)

/barcode/Euler_Totient_Ratio.png)
/d_curve/Euler_Totient_Ratio.png)








/phi_spectrum/Euler_Totient_Ratio.png)










/default/Euler_Totient_Ratio.png)
/default/Euler_Totient_Ratio.png)


| Nearest neighbor | Distance | |
|---|---|---|
| Noisy Period-2 | 4.64 | cross-origin |
| Logistic r=3.65 (Banded Chaos) | 5.14 | cross-origin |
| Fibonacci Quasicrystal | 5.33 | cross-origin |
Bispectrum › Bispectrum:off_diagonal_ratio | rank 304/306 | 0.1706 |
Chladni › Chladni:plate_low_mode_fraction | rank 303/306 | 0.0217 |
H4 600-Cell › H4 600-Cell:lattice_closure | rank 1/306 | 1.0000 |
SL(2,ℝ) (Thurston) › SL(2,ℝ) (Thurston):mean_trace | rank 305/306 | -1.9706 |
Symplectic › Symplectic:phase_reflection_symmetry | rank 304/306 | -0.0545 |