Metamath Proof Explorer


Theorem nnpw2blen

Description: A positive integer is between 2 to the power of its binary length minus 1 and 2 to the power of its binary length. (Contributed by AV, 31-May-2020)

Ref Expression
Assertion nnpw2blen N2#b N 1 N N<2#b N

Proof

Step Hyp Ref Expression
1 2rp 2+
2 1 a1i N2+
3 nnrp NN+
4 1ne2 12
5 4 necomi 21
6 5 a1i N21
7 relogbcl 2+N+21log2N
8 2 3 6 7 syl3anc Nlog2N
9 8 flcld Nlog2N
10 9 zcnd Nlog2N
11 pncan1 log2Nlog2N+1-1=log2N
12 10 11 syl Nlog2N+1-1=log2N
13 12 oveq2d N2log2N+1-1=2log2N
14 blennn N#b N = log2N+1
15 14 oveq1d N#b N 1 = log2N+1-1
16 15 oveq2d N2#b N 1 = 2log2N+1-1
17 2cnd N2
18 2ne0 20
19 18 a1i N20
20 17 19 9 cxpexpzd N2log2N=2log2N
21 13 16 20 3eqtr4d N2#b N 1 = 2log2N
22 flle log2Nlog2Nlog2N
23 8 22 syl Nlog2Nlog2N
24 2re 2
25 24 a1i N2
26 1lt2 1<2
27 26 a1i N1<2
28 9 zred Nlog2N
29 25 27 28 8 cxpled Nlog2Nlog2N2log2N2log2N
30 23 29 mpbid N2log2N2log2N
31 2cn 2
32 eldifpr 20122021
33 31 18 5 32 mpbir3an 201
34 nncn NN
35 nnne0 NN0
36 eldifsn N0NN0
37 34 35 36 sylanbrc NN0
38 cxplogb 201N02log2N=N
39 33 37 38 sylancr N2log2N=N
40 30 39 breqtrd N2log2NN
41 21 40 eqbrtrd N2#b N 1 N
42 flltp1 log2Nlog2N<log2N+1
43 8 42 syl Nlog2N<log2N+1
44 9 peano2zd Nlog2N+1
45 44 zred Nlog2N+1
46 25 27 8 45 cxpltd Nlog2N<log2N+12log2N<2log2N+1
47 43 46 mpbid N2log2N<2log2N+1
48 17 19 44 cxpexpzd N2log2N+1=2log2N+1
49 47 39 48 3brtr3d NN<2log2N+1
50 14 oveq2d N2#b N = 2log2N+1
51 49 50 breqtrrd NN<2#b N
52 41 51 jca N2#b N 1 N N<2#b N