theorem
proved
zeta_one
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IndisputableMonolith.NumberTheory.Primes.ArithmeticFunctions on GitHub at line 446.
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443 simp [sigma_apply]
444
445/-- ζ(1) = 1. -/
446theorem zeta_one : zeta 1 = 1 := by
447 exact zeta_apply (by decide)
448
449/-! ### Values at primes -/
450
451/-- ω(p) = 1 for prime p. -/
452theorem omega_prime {p : ℕ} (hp : Prime p) : omega p = 1 := by
453 have hp' : Nat.Prime p := (prime_iff p).1 hp
454 simp only [omega]
455 exact ArithmeticFunction.cardDistinctFactors_apply_prime hp'
456
457/-- Ω(p) = 1 for prime p. -/
458theorem bigOmega_prime {p : ℕ} (hp : Prime p) : bigOmega p = 1 := by
459 have hp' : Nat.Prime p := (prime_iff p).1 hp
460 exact ArithmeticFunction.cardFactors_apply_prime hp'
461
462/-! ### Additional totient values -/
463
464/-- φ(2) = 1. -/
465theorem totient_two : totient 2 = 1 := by
466 simp [totient]
467
468/-- φ(3) = 2. -/
469theorem totient_three : totient 3 = 2 := by
470 native_decide
471
472/-- φ(4) = 2. -/
473theorem totient_four : totient 4 = 2 := by
474 native_decide
475
476/-- φ(5) = 4. -/