BT0008 · Bertrand theorem

mul_assoc

Stable checked-use theorem · independently kernel verified

Multiplication is associative.

Current library: Alpha v34, 4,223 checked-use theorems; Stable remains 432. Historical first admissions, original proof editions, and non-admitted aliases are preserved. Exact original first-admission records.

Statement with defined notation

forall n m k. (n * m) * k = n * (m * k)

Every purple notation token opens its conservative definition. Expanding the displayed statement recovers the exact first-order Peano-arithmetic formula checked by the unchanged kernel.

Definitions used by this theorem

In the theorem statement

none

0 occurrences

In local proof propositions

none

0 occurrences

Exact expanded native-PA statement
forall n m k. (n * m) * k = n * (m * k)

Proof neighborhood

Direct theorem prerequisites

Direct theorem dependents

BT002A multiple_mul_right BT002C multiple_trans BT002F multiple_antisymm BT002H divides_remainder BT002I divides_linear_step BT0033 balanced_bezout_euclid_step BT0036 balanced_combination_scale_right BT0037 common_divisor_divides_balanced_result BT003S mod_eq_mul_right BT004F binary_crt BT004T mod_eq_of_mod_eq_multiple BT009X pow_add BT00BG coprime_product_is_lcm BT00QJ mul_shuffle_four BT00QK power_divides_exponent_antitone BT00QM power_divides_successor_of_cofactor BT00QN prime_power_successor_cancel_cofactor BT00QV pow_mul_base BT00RG double_triple_remainder_complement_budget BT00TU central_binom_succ_recurrence BT00TW factorial_weighted_product_combine BT00U0 four_power_central_recurrence_step BT00U3 four_pow_central_seed_package BT00UQ beta_product_prefix_suffix_split BT00VK central_binom_strong_upper_step BT00VL central_binom_recurrence_double_bundle BT00VP central_binom_odd_middle_le_four_pow BT00W7 linear_square_budget BT00WC bertrand_scaled_budget_root_36 BT00WD bertrand_scaled_budget_root_37 BT00WO pow_thirty_six_double_block_eq_pow_six_four_block_from_total BT00WP bertrand_h_root_32_from_total BT00WR bertrand_h_root_34_from_total BT00WS bertrand_h_root_35_from_total BT00WT bertrand_h_root_36_from_total BT00WU bertrand_h_root_37_from_total BT00WX scaled_factor_square_identity BT0101 prime_contribution_selected_successor_divides BT0115 bertrand_eventually_closed_upper BT011C scaled_remainder_lift BT011N prime_five_hundred_twenty_one BT0122 bertrand_cover_three_hundred_seventeen_five_hundred_twenty_one BT0123 bertrand_cutoff_lt_final_prime

Definition-aware tactic body

Only local propositions introduced by have or suffices are compacted. Every changed line has an exact-AST conservative-expansion receipt; the kernel still receives the immutable original tactic script.

Read the argument

Proof checkpoints

5 script commands · 2 reading checkpoints · 0 local claims

This is a reading aid, not a new proof or a proof-tree certificate. Checkpoint groups are consecutive commands, not inferred branch boundaries. Every step links to the preserved script.

Definition notation is shown below. Open the paired exact edition for the original native formulas. Source pairing is not a new equivalence certificate.

01Fix variables and assumptionsL1–2

Work with arbitrary variables or the premises of the current implication.

  1. L1
    intro n
  2. L2
    intro m
02Induction on kL3–5

Split the argument into the base and successor obligations. The induction hypothesis is available only in the successor branch.

  1. L3
    induction k
  2. L4
    simp
  3. L5
    simp [IH, mul_add]

Library-wide reading audit

Original defined command ledger · 5 lines
  1. 0001intro n
  2. 0002intro m
  3. 0003induction k
  4. 0004simp
  5. 0005simp [IH, mul_add]