Fill in the blanks with a single digit such that the resulting sentence is true.
"In this sentence, the number of occurences of the digit 0 is ______, of the digit 1 is ______, of the digit 2 is ______, of the digit 3 is ______, of even numbers is ______, of odd numbers is ______, and of prime numbers is ______."
1
, of the digit 1 is2
, of the digit 2 is3
, of the digit 3 is2
, of even numbers is5
, <---- of odd numbers is6
, and of prime numbers is7
.1
, of the digit 1 is2
, of the digit 2 is3
, of the digit 3 is2
, of even numbers is6
, <---- of odd numbers is5
, and of prime numbers is6
.a_0
,a_1
,a_2
,a_3
,a_{\text{ev}}
,a_{\text{od}}
, anda_{\text{pr}}
, respectively. Among these, the first four entries satisfya_i \geq 1
fori \leq 3
, while the other three entries each satisfya \geq 2
. Thus,a_0 = 1
,a_1 \geq 2
, anda_{\text{od}} \geq 3
. Givena_{\text{ev}} + a_{\text{od}} = 11
, the values have opposite parity, so thereβs at least one additional even and odd entry. Consequently,a_{\text{ev}} \geq 3
anda_{\text{od}} \geq 4
. This limits(a_{\text{ev}}, a_{\text{od}})
to only five pairs:(3,8), (4,7), (5,6), (6,5),
or(7,4)
. Each pair has exactly one prime number, hencea_{\text{pr}} \geq 3
, buta_{\text{pr}} \neq 3
, as this β3β would add a fourth prime to the set, implyinga_{\text{pr}} \geq 4
.a_2
anda_3
are potential placements for β1,β soa_1 \leq 4
. Ifa_1 = 4
, there are three primes, including one from(a_{\text{ev}}, a_{\text{od}})
, but nota_{\text{pr}}
. Settinga_{\text{pr}} = 4
would then leave only three primes, and any othera_{\text{pr}}
would be too large. Thus,a_1 \leq 3
. Assumea_1 = 3
; thena_3 \geq 2
. To assess feasibility, supposea_3 = 2
, which impliesa_2 \geq 2
, creating a contradiction witha_1 = 3
. Thus,a_3 \geq 3
. Ifa_3 \geq 4
,a_{\text{pr}} = 3
leads to more than three primes, soa_3 = 3
.a_3 = 3
, counting primes from(a_{\text{ev}}, a_{\text{od}})
yields five primes. Settinga_{\text{pr}} = 5
results in six primes, whilea_{\text{pr}} = 6
yields five primes, a contradiction. Therefore,a_1 = 2
, implyinga_2 \geq 3
becausea_2 = 2
would introduce three β2βs. Since onlya_3 = 2
allows a third 2, we concludea_2 = 3
anda_3 = 2
.a_{\text{pr}} = 6
ora_{\text{pr}} = 7
, resulting in two possible solutions:(1, 2, 3, 2, 6, 5, 6)
and(1, 2, 3, 2, 5, 6, 7)
.