π§© THE IMPOSSIBLE BLOCK 03 β BULL'S SECRET β SOLUTION
π§© THE IMPOSSIBLE BLOCK #03 β BULL'S SECRET β SOLUTION β THE TWO HIDDEN NUMBERS: 4 and 13 Sum = 17 Β· Product = 52 π BULL'S SECRET: Bull's sum is 17. And before anyone spoke, he knew every door of 17 was already LOCKED: every possible split gives a product that factors more than one way. Only 10 sums in the whole universe have that property. That hidden restriction is what made everything else possible. Rules: distinct integers from 2 to 99. Bull holds the SUM. Donkey holds the PRODUCT. Same logic as #02. 4,753 possible pairs. π§© 1. WHY THE FIRST POSSIBILITIES DISAPPEAR π« DONKEY: "I don't know." Any product with only ONE legal factorization is an OPEN door. Donkey would have known instantly, so those pairs die. 6 = 2Γ3 only Β· 8 = 2Γ4 only Β· 22 = 2Γ11 only Β· 77 = 7Γ11 only Every product of two different primes, and any product with a prime factor over 49 (like 53Γ4 = 212), is removed. 4,753 β 3,021 π§© 2. WHY BULL CAN MAKE HIS STATEMENT π BULL: "I knew you didn't know." Not maybe. Not probably. CERTAIN, from his sum alone. πͺ THE DOORS Every split of Bull's sum is a door. OPEN = the product factors one way only (Donkey would know). LOCKED = the product factors more than one way. Bull can only be certain if EVERY door of his sum is LOCKED. Bull's doors for 17, all locked: 2+15 β 30 = 3Γ10 π Β· 3+14 β 42 = 2Γ21 π Β· 4+13 β 52 = 2Γ26 π 5+12 β 60 = 3Γ20 π Β· 6+11 β 66 = 2Γ33 π Β· 7+10 β 70 = 2Γ35 π 8+9 β 72 = 3Γ24 π Sums with an OPEN door are eliminated: β’ Every even sum up to 54 β two different primes (8 = 3+5, 28 = 5+23, 54 = 7+47). Sum 6 too: 2+4 β 8. β’ Every odd sum where (sum β 2) is prime β 2Γprime (13 = 2+11 β 22). β’ 51 β 17+34 β 578 = 17Γ34 only. β’ Every sum from 55 to 196 except 194 β a prime from 53 to 97 (57 = 53+4 β 212 only; 106 = 59+47). β’ 194 β 95+99 β 9405 only. 197 β 98+99 β 9702 only. ONLY TEN SUMS HAVE EVERY DOOR LOCKED: 11, 17, 23, 27, 29, 35, 37, 41, 47, 53 3,021 β 145 π§©