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 (+5.0z) — beyond what the standard bank predicts for it. It sits beside Henon Near-Crisis (a=1.2) in the atlas (standard-bank rank 35) — a neighbor conventional features miss.
Heisenberg (Nil) (centered):area_length_ratio | +5.0z | bank-miss 1.5σ |
Heisenberg (Nil) (centered):xy_spread | +4.8z | bank-miss 2.1σ |
Gottwald-Melbourne:k_variance | +4.0z | bank-miss 1.6σ |
Bispectrum:off_diagonal_ratio | -3.3z | bank-miss 1.8σ |
Moiré:moire_integer_excess | +3.2z | bank-miss 1.0σ |
Möbius-S³:spinorial_asymmetry | +2.2z | bank-miss 3.8σ |








_(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 | 4.82 | cross-domain |
| Fibonacci Quasicrystal | 5.50 | |
| Henon Near-Crisis (a=1.2) | 5.53 | cross-domain |
Bispectrum › Bispectrum:off_diagonal_ratio | rank 296/298 | 0.1706 |
Chladni › Chladni:plate_low_mode_fraction | rank 295/298 | 0.0217 |
H4 600-Cell › H4 600-Cell:lattice_closure | rank 1/298 | 1.0000 |
Heisenberg (Nil) (centered) › Heisenberg (Nil) (centered):xy_aspect | rank 5/298 | 9.0724 |
Navier-Stokes › Navier-Stokes:intermittency_autocorr | rank 294/298 | -0.2973 |
SL(2,ℝ) (Thurston) › SL(2,ℝ) (Thurston):mean_trace | rank 296/298 | -1.9706 |
Symplectic › Symplectic:phase_reflection_symmetry | rank 296/298 | -0.0545 |