fldiv4p1lem1div2 - Metamath Proof Explorer

	Metamath Proof Explorer		< Previous Next > Nearby theorems
Mirrors > Home > MPE Home > Th. List > fldiv4p1lem1div2		Structured version Visualization version GIF version

Theorem fldiv4p1lem1div2 13846

Description: The floor of an integer equal to 3 or greater than 4, increased by 1, is less than or equal to the half of the integer minus 1. (Contributed by AV, 8-Jul-2021.)

**Assertion**
Ref	Expression
fldiv4p1lem1div2	⊢ ((𝑁 = 3 ∨ 𝑁 ∈ (ℤ_≥‘5)) → ((⌊‘(𝑁 / 4)) + 1) ≤ ((𝑁 − 1) / 2))

**Proof of Theorem fldiv4p1lem1div2**
Step	Hyp	Ref	Expression
1		1le1 11816	. . . 4 ⊢ 1 ≤ 1
2	1	a1i 11	. . 3 ⊢ (𝑁 = 3 → 1 ≤ 1)
3		fvoveq1 7420	. . . . . 6 ⊢ (𝑁 = 3 → (⌊‘(𝑁 / 4)) = (⌊‘(3 / 4)))
4		3lt4 12395	. . . . . . 7 ⊢ 3 < 4
5		3nn0 12500	. . . . . . . 8 ⊢ 3 ∈ ℕ₀
6		4nn 12302	. . . . . . . 8 ⊢ 4 ∈ ℕ
7		divfl0 13835	. . . . . . . 8 ⊢ ((3 ∈ ℕ₀ ∧ 4 ∈ ℕ) → (3 < 4 ↔ (⌊‘(3 / 4)) = 0))
8	5, 6, 7	mp2an 702	. . . . . . 7 ⊢ (3 < 4 ↔ (⌊‘(3 / 4)) = 0)
9	4, 8	mpbi 232	. . . . . 6 ⊢ (⌊‘(3 / 4)) = 0
10	3, 9	eqtrdi 2814	. . . . 5 ⊢ (𝑁 = 3 → (⌊‘(𝑁 / 4)) = 0)
11	10	oveq1d 7412	. . . 4 ⊢ (𝑁 = 3 → ((⌊‘(𝑁 / 4)) + 1) = (0 + 1))
12		0p1e1 12339	. . . 4 ⊢ (0 + 1) = 1
13	11, 12	eqtrdi 2814	. . 3 ⊢ (𝑁 = 3 → ((⌊‘(𝑁 / 4)) + 1) = 1)
14		oveq1 7404	. . . . . 6 ⊢ (𝑁 = 3 → (𝑁 − 1) = (3 − 1))
15		3m1e2 12346	. . . . . 6 ⊢ (3 − 1) = 2
16	14, 15	eqtrdi 2814	. . . . 5 ⊢ (𝑁 = 3 → (𝑁 − 1) = 2)
17	16	oveq1d 7412	. . . 4 ⊢ (𝑁 = 3 → ((𝑁 − 1) / 2) = (2 / 2))
18		2div2e1 12359	. . . 4 ⊢ (2 / 2) = 1
19	17, 18	eqtrdi 2814	. . 3 ⊢ (𝑁 = 3 → ((𝑁 − 1) / 2) = 1)
20	2, 13, 19	3brtr4d 5133	. 2 ⊢ (𝑁 = 3 → ((⌊‘(𝑁 / 4)) + 1) ≤ ((𝑁 − 1) / 2))
21		uzp1 12877	. . 3 ⊢ (𝑁 ∈ (ℤ_≥‘5) → (𝑁 = 5 ∨ 𝑁 ∈ (ℤ_≥‘(5 + 1))))
22		2re 12293	. . . . . . 7 ⊢ 2 ∈ ℝ
23	22	leidi 11722	. . . . . 6 ⊢ 2 ≤ 2
24	23	a1i 11	. . . . 5 ⊢ (𝑁 = 5 → 2 ≤ 2)
25		fvoveq1 7420	. . . . . . . 8 ⊢ (𝑁 = 5 → (⌊‘(𝑁 / 4)) = (⌊‘(5 / 4)))
26		df-5 12284	. . . . . . . . . . . 12 ⊢ 5 = (4 + 1)
27	26	oveq1i 7407	. . . . . . . . . . 11 ⊢ (5 / 4) = ((4 + 1) / 4)
28		4cn 12304	. . . . . . . . . . . 12 ⊢ 4 ∈ ℂ
29		ax-1cn 11132	. . . . . . . . . . . 12 ⊢ 1 ∈ ℂ
30		4ne0 12330	. . . . . . . . . . . 12 ⊢ 4 ≠ 0
31	28, 29, 28, 30	divdiri 11949	. . . . . . . . . . 11 ⊢ ((4 + 1) / 4) = ((4 / 4) + (1 / 4))
32	28, 30	dividi 11925	. . . . . . . . . . . 12 ⊢ (4 / 4) = 1
33	32	oveq1i 7407	. . . . . . . . . . 11 ⊢ ((4 / 4) + (1 / 4)) = (1 + (1 / 4))
34	27, 31, 33	3eqtri 2790	. . . . . . . . . 10 ⊢ (5 / 4) = (1 + (1 / 4))
35	34	fveq2i 6871	. . . . . . . . 9 ⊢ (⌊‘(5 / 4)) = (⌊‘(1 + (1 / 4)))
36		1re 11182	. . . . . . . . . . 11 ⊢ 1 ∈ ℝ
37		0le1 11711	. . . . . . . . . . 11 ⊢ 0 ≤ 1
38		4re 12303	. . . . . . . . . . 11 ⊢ 4 ∈ ℝ
39		4pos 12329	. . . . . . . . . . 11 ⊢ 0 < 4
40		divge0 12062	. . . . . . . . . . 11 ⊢ (((1 ∈ ℝ ∧ 0 ≤ 1) ∧ (4 ∈ ℝ ∧ 0 < 4)) → 0 ≤ (1 / 4))
41	36, 37, 38, 39, 40	mp4an 703	. . . . . . . . . 10 ⊢ 0 ≤ (1 / 4)
42		1lt4 12397	. . . . . . . . . . 11 ⊢ 1 < 4
43		recgt1 12089	. . . . . . . . . . . 12 ⊢ ((4 ∈ ℝ ∧ 0 < 4) → (1 < 4 ↔ (1 / 4) < 1))
44	38, 39, 43	mp2an 702	. . . . . . . . . . 11 ⊢ (1 < 4 ↔ (1 / 4) < 1)
45	42, 44	mpbi 232	. . . . . . . . . 10 ⊢ (1 / 4) < 1
46		1z 12602	. . . . . . . . . . 11 ⊢ 1 ∈ ℤ
47	38, 30	rereccli 11957	. . . . . . . . . . 11 ⊢ (1 / 4) ∈ ℝ
48		flbi2 13828	. . . . . . . . . . 11 ⊢ ((1 ∈ ℤ ∧ (1 / 4) ∈ ℝ) → ((⌊‘(1 + (1 / 4))) = 1 ↔ (0 ≤ (1 / 4) ∧ (1 / 4) < 1)))
49	46, 47, 48	mp2an 702	. . . . . . . . . 10 ⊢ ((⌊‘(1 + (1 / 4))) = 1 ↔ (0 ≤ (1 / 4) ∧ (1 / 4) < 1))
50	41, 45, 49	mpbir2an 721	. . . . . . . . 9 ⊢ (⌊‘(1 + (1 / 4))) = 1
51	35, 50	eqtri 2786	. . . . . . . 8 ⊢ (⌊‘(5 / 4)) = 1
52	25, 51	eqtrdi 2814	. . . . . . 7 ⊢ (𝑁 = 5 → (⌊‘(𝑁 / 4)) = 1)
53	52	oveq1d 7412	. . . . . 6 ⊢ (𝑁 = 5 → ((⌊‘(𝑁 / 4)) + 1) = (1 + 1))
54		1p1e2 12342	. . . . . 6 ⊢ (1 + 1) = 2
55	53, 54	eqtrdi 2814	. . . . 5 ⊢ (𝑁 = 5 → ((⌊‘(𝑁 / 4)) + 1) = 2)
56		oveq1 7404	. . . . . . . 8 ⊢ (𝑁 = 5 → (𝑁 − 1) = (5 − 1))
57		5m1e4 12348	. . . . . . . 8 ⊢ (5 − 1) = 4
58	56, 57	eqtrdi 2814	. . . . . . 7 ⊢ (𝑁 = 5 → (𝑁 − 1) = 4)
59	58	oveq1d 7412	. . . . . 6 ⊢ (𝑁 = 5 → ((𝑁 − 1) / 2) = (4 / 2))
60		4div2e2 12390	. . . . . 6 ⊢ (4 / 2) = 2
61	59, 60	eqtrdi 2814	. . . . 5 ⊢ (𝑁 = 5 → ((𝑁 − 1) / 2) = 2)
62	24, 55, 61	3brtr4d 5133	. . . 4 ⊢ (𝑁 = 5 → ((⌊‘(𝑁 / 4)) + 1) ≤ ((𝑁 − 1) / 2))
63		eluz2 12846	. . . . . 6 ⊢ (𝑁 ∈ (ℤ_≥‘6) ↔ (6 ∈ ℤ ∧ 𝑁 ∈ ℤ ∧ 6 ≤ 𝑁))
64		zre 12573	. . . . . . . . . . 11 ⊢ (𝑁 ∈ ℤ → 𝑁 ∈ ℝ)
65		id 22	. . . . . . . . . . . 12 ⊢ (𝑁 ∈ ℝ → 𝑁 ∈ ℝ)
66	38	a1i 11	. . . . . . . . . . . 12 ⊢ (𝑁 ∈ ℝ → 4 ∈ ℝ)
67	30	a1i 11	. . . . . . . . . . . 12 ⊢ (𝑁 ∈ ℝ → 4 ≠ 0)
68	65, 66, 67	redivcld 12020	. . . . . . . . . . 11 ⊢ (𝑁 ∈ ℝ → (𝑁 / 4) ∈ ℝ)
69		flle 13810	. . . . . . . . . . 11 ⊢ ((𝑁 / 4) ∈ ℝ → (⌊‘(𝑁 / 4)) ≤ (𝑁 / 4))
70	64, 68, 69	3syl 18	. . . . . . . . . 10 ⊢ (𝑁 ∈ ℤ → (⌊‘(𝑁 / 4)) ≤ (𝑁 / 4))
71	70	adantr 484	. . . . . . . . 9 ⊢ ((𝑁 ∈ ℤ ∧ 6 ≤ 𝑁) → (⌊‘(𝑁 / 4)) ≤ (𝑁 / 4))
72	68	flcld 13809	. . . . . . . . . . . . . 14 ⊢ (𝑁 ∈ ℝ → (⌊‘(𝑁 / 4)) ∈ ℤ)
73	72	zred 12678	. . . . . . . . . . . . 13 ⊢ (𝑁 ∈ ℝ → (⌊‘(𝑁 / 4)) ∈ ℝ)
74	36	a1i 11	. . . . . . . . . . . . 13 ⊢ (𝑁 ∈ ℝ → 1 ∈ ℝ)
75	73, 68, 74	3jca 1142	. . . . . . . . . . . 12 ⊢ (𝑁 ∈ ℝ → ((⌊‘(𝑁 / 4)) ∈ ℝ ∧ (𝑁 / 4) ∈ ℝ ∧ 1 ∈ ℝ))
76	64, 75	syl 17	. . . . . . . . . . 11 ⊢ (𝑁 ∈ ℤ → ((⌊‘(𝑁 / 4)) ∈ ℝ ∧ (𝑁 / 4) ∈ ℝ ∧ 1 ∈ ℝ))
77	76	adantr 484	. . . . . . . . . 10 ⊢ ((𝑁 ∈ ℤ ∧ 6 ≤ 𝑁) → ((⌊‘(𝑁 / 4)) ∈ ℝ ∧ (𝑁 / 4) ∈ ℝ ∧ 1 ∈ ℝ))
78		leadd1 11656	. . . . . . . . . 10 ⊢ (((⌊‘(𝑁 / 4)) ∈ ℝ ∧ (𝑁 / 4) ∈ ℝ ∧ 1 ∈ ℝ) → ((⌊‘(𝑁 / 4)) ≤ (𝑁 / 4) ↔ ((⌊‘(𝑁 / 4)) + 1) ≤ ((𝑁 / 4) + 1)))
79	77, 78	syl 17	. . . . . . . . 9 ⊢ ((𝑁 ∈ ℤ ∧ 6 ≤ 𝑁) → ((⌊‘(𝑁 / 4)) ≤ (𝑁 / 4) ↔ ((⌊‘(𝑁 / 4)) + 1) ≤ ((𝑁 / 4) + 1)))
80	71, 79	mpbid 234	. . . . . . . 8 ⊢ ((𝑁 ∈ ℤ ∧ 6 ≤ 𝑁) → ((⌊‘(𝑁 / 4)) + 1) ≤ ((𝑁 / 4) + 1))
81		div4p1lem1div2 12477	. . . . . . . . 9 ⊢ ((𝑁 ∈ ℝ ∧ 6 ≤ 𝑁) → ((𝑁 / 4) + 1) ≤ ((𝑁 − 1) / 2))
82	64, 81	sylan 589	. . . . . . . 8 ⊢ ((𝑁 ∈ ℤ ∧ 6 ≤ 𝑁) → ((𝑁 / 4) + 1) ≤ ((𝑁 − 1) / 2))
83		peano2re 11357	. . . . . . . . . . . . 13 ⊢ ((⌊‘(𝑁 / 4)) ∈ ℝ → ((⌊‘(𝑁 / 4)) + 1) ∈ ℝ)
84	73, 83	syl 17	. . . . . . . . . . . 12 ⊢ (𝑁 ∈ ℝ → ((⌊‘(𝑁 / 4)) + 1) ∈ ℝ)
85		peano2re 11357	. . . . . . . . . . . . 13 ⊢ ((𝑁 / 4) ∈ ℝ → ((𝑁 / 4) + 1) ∈ ℝ)
86	68, 85	syl 17	. . . . . . . . . . . 12 ⊢ (𝑁 ∈ ℝ → ((𝑁 / 4) + 1) ∈ ℝ)
87		peano2rem 11499	. . . . . . . . . . . . 13 ⊢ (𝑁 ∈ ℝ → (𝑁 − 1) ∈ ℝ)
88	87	rehalfcld 12469	. . . . . . . . . . . 12 ⊢ (𝑁 ∈ ℝ → ((𝑁 − 1) / 2) ∈ ℝ)
89	84, 86, 88	3jca 1142	. . . . . . . . . . 11 ⊢ (𝑁 ∈ ℝ → (((⌊‘(𝑁 / 4)) + 1) ∈ ℝ ∧ ((𝑁 / 4) + 1) ∈ ℝ ∧ ((𝑁 − 1) / 2) ∈ ℝ))
90	64, 89	syl 17	. . . . . . . . . 10 ⊢ (𝑁 ∈ ℤ → (((⌊‘(𝑁 / 4)) + 1) ∈ ℝ ∧ ((𝑁 / 4) + 1) ∈ ℝ ∧ ((𝑁 − 1) / 2) ∈ ℝ))
91	90	adantr 484	. . . . . . . . 9 ⊢ ((𝑁 ∈ ℤ ∧ 6 ≤ 𝑁) → (((⌊‘(𝑁 / 4)) + 1) ∈ ℝ ∧ ((𝑁 / 4) + 1) ∈ ℝ ∧ ((𝑁 − 1) / 2) ∈ ℝ))
92		letr 11278	. . . . . . . . 9 ⊢ ((((⌊‘(𝑁 / 4)) + 1) ∈ ℝ ∧ ((𝑁 / 4) + 1) ∈ ℝ ∧ ((𝑁 − 1) / 2) ∈ ℝ) → ((((⌊‘(𝑁 / 4)) + 1) ≤ ((𝑁 / 4) + 1) ∧ ((𝑁 / 4) + 1) ≤ ((𝑁 − 1) / 2)) → ((⌊‘(𝑁 / 4)) + 1) ≤ ((𝑁 − 1) / 2)))
93	91, 92	syl 17	. . . . . . . 8 ⊢ ((𝑁 ∈ ℤ ∧ 6 ≤ 𝑁) → ((((⌊‘(𝑁 / 4)) + 1) ≤ ((𝑁 / 4) + 1) ∧ ((𝑁 / 4) + 1) ≤ ((𝑁 − 1) / 2)) → ((⌊‘(𝑁 / 4)) + 1) ≤ ((𝑁 − 1) / 2)))
94	80, 82, 93	mp2and 709	. . . . . . 7 ⊢ ((𝑁 ∈ ℤ ∧ 6 ≤ 𝑁) → ((⌊‘(𝑁 / 4)) + 1) ≤ ((𝑁 − 1) / 2))
95	94	3adant1 1144	. . . . . 6 ⊢ ((6 ∈ ℤ ∧ 𝑁 ∈ ℤ ∧ 6 ≤ 𝑁) → ((⌊‘(𝑁 / 4)) + 1) ≤ ((𝑁 − 1) / 2))
96	63, 95	sylbi 219	. . . . 5 ⊢ (𝑁 ∈ (ℤ_≥‘6) → ((⌊‘(𝑁 / 4)) + 1) ≤ ((𝑁 − 1) / 2))
97		5p1e6 12365	. . . . . 6 ⊢ (5 + 1) = 6
98	97	fveq2i 6871	. . . . 5 ⊢ (ℤ_≥‘(5 + 1)) = (ℤ_≥‘6)
99	96, 98	eleq2s 2881	. . . 4 ⊢ (𝑁 ∈ (ℤ_≥‘(5 + 1)) → ((⌊‘(𝑁 / 4)) + 1) ≤ ((𝑁 − 1) / 2))
100	62, 99	jaoi 868	. . 3 ⊢ ((𝑁 = 5 ∨ 𝑁 ∈ (ℤ_≥‘(5 + 1))) → ((⌊‘(𝑁 / 4)) + 1) ≤ ((𝑁 − 1) / 2))
101	21, 100	syl 17	. 2 ⊢ (𝑁 ∈ (ℤ_≥‘5) → ((⌊‘(𝑁 / 4)) + 1) ≤ ((𝑁 − 1) / 2))
102	20, 101	jaoi 868	1 ⊢ ((𝑁 = 3 ∨ 𝑁 ∈ (ℤ_≥‘5)) → ((⌊‘(𝑁 / 4)) + 1) ≤ ((𝑁 − 1) / 2))

Colors of variables: wff setvar class

Syntax hints: → wi 4 ↔ wb 208 ∧ wa 399 ∨ wo 858 ∧ w3a 1099 = wceq 1561 ∈ wcel 2143 ≠ wne 2958 class class class wbr 5101 ‘cfv 6522 (class class class)co 7397 ℝcr 11073 0cc0 11074 1c1 11075 + caddc 11077 < clt 11217 ≤ cle 11218 − cmin 11415 / cdiv 11845 ℕcn 12211 2c2 12273 3c3 12274 4c4 12275 5c5 12276 6c6 12277 ℕ₀cn0 12482 ℤcz 12569 ℤ_≥cuz 12840 ⌊cfl 13801

This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1816 ax-4 1830 ax-5 1931 ax-6 1988 ax-7 2029 ax-8 2145 ax-9 2153 ax-10 2176 ax-11 2192 ax-12 2213 ax-ext 2735 ax-sep 5247 ax-nul 5257 ax-pow 5323 ax-pr 5391 ax-un 7719 ax-cnex 11130 ax-resscn 11131 ax-1cn 11132 ax-icn 11133 ax-addcl 11134 ax-addrcl 11135 ax-mulcl 11136 ax-mulrcl 11137 ax-mulcom 11138 ax-addass 11139 ax-mulass 11140 ax-distr 11141 ax-i2m1 11142 ax-1ne0 11143 ax-1rid 11144 ax-rnegex 11145 ax-rrecex 11146 ax-cnre 11147 ax-pre-lttri 11148 ax-pre-lttrn 11149 ax-pre-ltadd 11150 ax-pre-mulgt0 11151 ax-pre-sup 11152

This theorem depends on definitions: df-bi 209 df-an 400 df-or 859 df-3or 1100 df-3an 1101 df-tru 1564 df-fal 1574 df-ex 1801 df-nf 1805 df-sb 2092 df-mo 2567 df-eu 2597 df-clab 2742 df-cleq 2755 df-clel 2838 df-nfc 2912 df-ne 2959 df-nel 3063 df-ral 3078 df-rex 3088 df-rmo 3368 df-reu 3369 df-rab 3416 df-v 3457 df-sbc 3746 df-csb 3854 df-dif 3908 df-un 3910 df-in 3912 df-ss 3922 df-pss 3925 df-nul 4287 df-if 4482 df-pw 4558 df-sn 4584 df-pr 4586 df-op 4590 df-uni 4867 df-iun 4952 df-br 5102 df-opab 5164 df-mpt 5183 df-tr 5209 df-id 5543 df-eprel 5548 df-po 5556 df-so 5557 df-fr 5601 df-we 5603 df-xp 5654 df-rel 5655 df-cnv 5656 df-co 5657 df-dm 5658 df-rn 5659 df-res 5660 df-ima 5661 df-pred 6289 df-ord 6350 df-on 6351 df-lim 6352 df-suc 6353 df-iota 6478 df-fun 6524 df-fn 6525 df-f 6526 df-f1 6527 df-fo 6528 df-f1o 6529 df-fv 6530 df-riota 7354 df-ov 7400 df-oprab 7401 df-mpo 7402 df-om 7848 df-2nd 7972 df-frecs 8263 df-wrecs 8294 df-recs 8343 df-rdg 8382 df-er 8679 df-en 8929 df-dom 8930 df-sdom 8931 df-sup 9389 df-inf 9390 df-pnf 11219 df-mnf 11220 df-xr 11221 df-ltxr 11222 df-le 11223 df-sub 11417 df-neg 11418 df-div 11846 df-nn 12212 df-2 12281 df-3 12282 df-4 12283 df-5 12284 df-6 12285 df-n0 12483 df-z 12570 df-uz 12841 df-rp 12995 df-fl 13803

This theorem is referenced by: gausslemma2dlem0f 27426

W3C validator