Here's the countdown, skipping primes and 12:
100, 99, 98, 97 (prime, skipped), 96, 95, 94, 93, 92, 91, 90, 89 (prime, skipped), 88, 87, 86, 85, 84, 83 (prime, skipped), 82, 81, 80, 79 (prime, skipped), 78, 77, 76, 75, 74, 73 (prime, skipped), 72, 71 (prime, skipped), 70, 69, 68, 67 (prime, skipped), 66, 65, 64, 63, 62, 61 (prime, skipped), 60, 59 (prime, skipped), 58, 57, 56, 55, 54, 53 (prime, skipped), 52, 51, 50, 49, 48, 47 (prime, skipped), 46, 45, 44, 43 (prime, skipped), 42, 41 (prime, skipped), 40, 39, 38, 37 (prime, skipped), 36, 35, 34, 33, 32, 31 (prime, skipped), 30, 29 (prime, skipped), 28, 27, 26, 25, 24, 23 (prime, skipped), 22, 21, 20, 19 (prime, skipped), 18, 17 (prime, skipped), 16, 15, 14, 13 (prime, skipped), 11 (prime, skipped), 10, 9, 8, 7 (prime, skipped), 6, 5 (prime, skipped), 4, 3 (prime, skipped), 2 (prime, skipped), 1