Lemma HMAC_DRBG_generate_helper_Z_incremental_equiv: forall HMAC key v z incr, 0 <= z -> 0 < incr <= 32 -> (exists n, z = n * 32) -> HMAC_DRBG_generate_helper_Z HMAC key v (z + incr) = HMAC_DRBG_generate_helper_Z HMAC key v (z + 32).