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card_divisors_prime_pow
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IndisputableMonolith.NumberTheory.Primes.ArithmeticFunctions on GitHub at line 546.
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543 exact Nat.divisors_prime_pow hp' k
544
545/-- The number of divisors of p^k is k + 1. -/
546theorem card_divisors_prime_pow {p k : ℕ} (hp : Prime p) : (p ^ k).divisors.card = k + 1 := by
547 rw [divisors_prime_pow hp]
548 simp
549
550/-! ### Additional small prime facts -/
551
552theorem prime_twentythree : Prime 23 := by decide
553theorem prime_twentynine : Prime 29 := by decide
554theorem prime_thirtyone : Prime 31 := by decide
555theorem prime_fortyone : Prime 41 := by decide
556theorem prime_fortythree : Prime 43 := by decide
557theorem prime_fortyseven : Prime 47 := by decide
558theorem prime_fiftythree : Prime 53 := by decide
559theorem prime_fiftynine : Prime 59 := by decide
560theorem prime_sixtyone : Prime 61 := by decide
561theorem prime_sixtyseven : Prime 67 := by decide
562theorem prime_seventyone : Prime 71 := by decide
563theorem prime_seventythree : Prime 73 := by decide
564theorem prime_seventynine : Prime 79 := by decide
565theorem prime_eightythree : Prime 83 := by decide
566theorem prime_eightynine : Prime 89 := by decide
567theorem prime_ninetyseven : Prime 97 := by decide
568
569/-! ### Factorial valuations (decidable facts) -/
570
571/-- vp 2 (4!) = 3. -/
572theorem vp_factorial_four_two : vp 2 (Nat.factorial 4) = 3 := by native_decide
573
574/-- vp 2 (5!) = 3. -/
575theorem vp_factorial_five_two : vp 2 (Nat.factorial 5) = 3 := by native_decide
576