MPE Home Metamath Proof Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >  facubnd Unicode version

Theorem facubnd 11519
Description: An upper bound for the factorial function. (Contributed by Mario Carneiro, 15-Apr-2016.)
Assertion
Ref Expression
facubnd  |-  ( N  e.  NN0  ->  ( ! `
 N )  <_ 
( N ^ N
) )

Proof of Theorem facubnd
Dummy variables  m  k are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 fveq2 5669 . . . 4  |-  ( m  =  0  ->  ( ! `  m )  =  ( ! ` 
0 ) )
2 fac0 11497 . . . 4  |-  ( ! `
 0 )  =  1
31, 2syl6eq 2436 . . 3  |-  ( m  =  0  ->  ( ! `  m )  =  1 )
4 id 20 . . . . 5  |-  ( m  =  0  ->  m  =  0 )
54, 4oveq12d 6039 . . . 4  |-  ( m  =  0  ->  (
m ^ m )  =  ( 0 ^ 0 ) )
6 0cn 9018 . . . . 5  |-  0  e.  CC
7 exp0 11314 . . . . 5  |-  ( 0  e.  CC  ->  (
0 ^ 0 )  =  1 )
86, 7ax-mp 8 . . . 4  |-  ( 0 ^ 0 )  =  1
95, 8syl6eq 2436 . . 3  |-  ( m  =  0  ->  (
m ^ m )  =  1 )
103, 9breq12d 4167 . 2  |-  ( m  =  0  ->  (
( ! `  m
)  <_  ( m ^ m )  <->  1  <_  1 ) )
11 fveq2 5669 . . 3  |-  ( m  =  k  ->  ( ! `  m )  =  ( ! `  k ) )
12 id 20 . . . 4  |-  ( m  =  k  ->  m  =  k )
1312, 12oveq12d 6039 . . 3  |-  ( m  =  k  ->  (
m ^ m )  =  ( k ^
k ) )
1411, 13breq12d 4167 . 2  |-  ( m  =  k  ->  (
( ! `  m
)  <_  ( m ^ m )  <->  ( ! `  k )  <_  (
k ^ k ) ) )
15 fveq2 5669 . . 3  |-  ( m  =  ( k  +  1 )  ->  ( ! `  m )  =  ( ! `  ( k  +  1 ) ) )
16 id 20 . . . 4  |-  ( m  =  ( k  +  1 )  ->  m  =  ( k  +  1 ) )
1716, 16oveq12d 6039 . . 3  |-  ( m  =  ( k  +  1 )  ->  (
m ^ m )  =  ( ( k  +  1 ) ^
( k  +  1 ) ) )
1815, 17breq12d 4167 . 2  |-  ( m  =  ( k  +  1 )  ->  (
( ! `  m
)  <_  ( m ^ m )  <->  ( ! `  ( k  +  1 ) )  <_  (
( k  +  1 ) ^ ( k  +  1 ) ) ) )
19 fveq2 5669 . . 3  |-  ( m  =  N  ->  ( ! `  m )  =  ( ! `  N ) )
20 id 20 . . . 4  |-  ( m  =  N  ->  m  =  N )
2120, 20oveq12d 6039 . . 3  |-  ( m  =  N  ->  (
m ^ m )  =  ( N ^ N ) )
2219, 21breq12d 4167 . 2  |-  ( m  =  N  ->  (
( ! `  m
)  <_  ( m ^ m )  <->  ( ! `  N )  <_  ( N ^ N ) ) )
23 1le1 9583 . 2  |-  1  <_  1
24 faccl 11504 . . . . . . . 8  |-  ( k  e.  NN0  ->  ( ! `
 k )  e.  NN )
2524adantr 452 . . . . . . 7  |-  ( ( k  e.  NN0  /\  ( ! `  k )  <_  ( k ^
k ) )  -> 
( ! `  k
)  e.  NN )
2625nnred 9948 . . . . . 6  |-  ( ( k  e.  NN0  /\  ( ! `  k )  <_  ( k ^
k ) )  -> 
( ! `  k
)  e.  RR )
27 nn0re 10163 . . . . . . . 8  |-  ( k  e.  NN0  ->  k  e.  RR )
2827adantr 452 . . . . . . 7  |-  ( ( k  e.  NN0  /\  ( ! `  k )  <_  ( k ^
k ) )  -> 
k  e.  RR )
29 simpl 444 . . . . . . 7  |-  ( ( k  e.  NN0  /\  ( ! `  k )  <_  ( k ^
k ) )  -> 
k  e.  NN0 )
3028, 29reexpcld 11468 . . . . . 6  |-  ( ( k  e.  NN0  /\  ( ! `  k )  <_  ( k ^
k ) )  -> 
( k ^ k
)  e.  RR )
31 nn0p1nn 10192 . . . . . . . . 9  |-  ( k  e.  NN0  ->  ( k  +  1 )  e.  NN )
3231adantr 452 . . . . . . . 8  |-  ( ( k  e.  NN0  /\  ( ! `  k )  <_  ( k ^
k ) )  -> 
( k  +  1 )  e.  NN )
3332nnred 9948 . . . . . . 7  |-  ( ( k  e.  NN0  /\  ( ! `  k )  <_  ( k ^
k ) )  -> 
( k  +  1 )  e.  RR )
3433, 29reexpcld 11468 . . . . . 6  |-  ( ( k  e.  NN0  /\  ( ! `  k )  <_  ( k ^
k ) )  -> 
( ( k  +  1 ) ^ k
)  e.  RR )
35 simpr 448 . . . . . 6  |-  ( ( k  e.  NN0  /\  ( ! `  k )  <_  ( k ^
k ) )  -> 
( ! `  k
)  <_  ( k ^ k ) )
36 nn0ge0 10180 . . . . . . . 8  |-  ( k  e.  NN0  ->  0  <_ 
k )
3736adantr 452 . . . . . . 7  |-  ( ( k  e.  NN0  /\  ( ! `  k )  <_  ( k ^
k ) )  -> 
0  <_  k )
3828lep1d 9875 . . . . . . 7  |-  ( ( k  e.  NN0  /\  ( ! `  k )  <_  ( k ^
k ) )  -> 
k  <_  ( k  +  1 ) )
39 leexp1a 11366 . . . . . . 7  |-  ( ( ( k  e.  RR  /\  ( k  +  1 )  e.  RR  /\  k  e.  NN0 )  /\  ( 0  <_  k  /\  k  <_  ( k  +  1 ) ) )  ->  ( k ^ k )  <_ 
( ( k  +  1 ) ^ k
) )
4028, 33, 29, 37, 38, 39syl32anc 1192 . . . . . 6  |-  ( ( k  e.  NN0  /\  ( ! `  k )  <_  ( k ^
k ) )  -> 
( k ^ k
)  <_  ( (
k  +  1 ) ^ k ) )
4126, 30, 34, 35, 40letrd 9160 . . . . 5  |-  ( ( k  e.  NN0  /\  ( ! `  k )  <_  ( k ^
k ) )  -> 
( ! `  k
)  <_  ( (
k  +  1 ) ^ k ) )
4232nngt0d 9976 . . . . . 6  |-  ( ( k  e.  NN0  /\  ( ! `  k )  <_  ( k ^
k ) )  -> 
0  <  ( k  +  1 ) )
43 lemul1 9795 . . . . . 6  |-  ( ( ( ! `  k
)  e.  RR  /\  ( ( k  +  1 ) ^ k
)  e.  RR  /\  ( ( k  +  1 )  e.  RR  /\  0  <  ( k  +  1 ) ) )  ->  ( ( ! `  k )  <_  ( ( k  +  1 ) ^ k
)  <->  ( ( ! `
 k )  x.  ( k  +  1 ) )  <_  (
( ( k  +  1 ) ^ k
)  x.  ( k  +  1 ) ) ) )
4426, 34, 33, 42, 43syl112anc 1188 . . . . 5  |-  ( ( k  e.  NN0  /\  ( ! `  k )  <_  ( k ^
k ) )  -> 
( ( ! `  k )  <_  (
( k  +  1 ) ^ k )  <-> 
( ( ! `  k )  x.  (
k  +  1 ) )  <_  ( (
( k  +  1 ) ^ k )  x.  ( k  +  1 ) ) ) )
4541, 44mpbid 202 . . . 4  |-  ( ( k  e.  NN0  /\  ( ! `  k )  <_  ( k ^
k ) )  -> 
( ( ! `  k )  x.  (
k  +  1 ) )  <_  ( (
( k  +  1 ) ^ k )  x.  ( k  +  1 ) ) )
46 facp1 11499 . . . . 5  |-  ( k  e.  NN0  ->  ( ! `
 ( k  +  1 ) )  =  ( ( ! `  k )  x.  (
k  +  1 ) ) )
4746adantr 452 . . . 4  |-  ( ( k  e.  NN0  /\  ( ! `  k )  <_  ( k ^
k ) )  -> 
( ! `  (
k  +  1 ) )  =  ( ( ! `  k )  x.  ( k  +  1 ) ) )
4832nncnd 9949 . . . . 5  |-  ( ( k  e.  NN0  /\  ( ! `  k )  <_  ( k ^
k ) )  -> 
( k  +  1 )  e.  CC )
4948, 29expp1d 11452 . . . 4  |-  ( ( k  e.  NN0  /\  ( ! `  k )  <_  ( k ^
k ) )  -> 
( ( k  +  1 ) ^ (
k  +  1 ) )  =  ( ( ( k  +  1 ) ^ k )  x.  ( k  +  1 ) ) )
5045, 47, 493brtr4d 4184 . . 3  |-  ( ( k  e.  NN0  /\  ( ! `  k )  <_  ( k ^
k ) )  -> 
( ! `  (
k  +  1 ) )  <_  ( (
k  +  1 ) ^ ( k  +  1 ) ) )
5150ex 424 . 2  |-  ( k  e.  NN0  ->  ( ( ! `  k )  <_  ( k ^
k )  ->  ( ! `  ( k  +  1 ) )  <_  ( ( k  +  1 ) ^
( k  +  1 ) ) ) )
5210, 14, 18, 22, 23, 51nn0ind 10299 1  |-  ( N  e.  NN0  ->  ( ! `
 N )  <_ 
( N ^ N
) )
Colors of variables: wff set class
Syntax hints:    -> wi 4    <-> wb 177    /\ wa 359    = wceq 1649    e. wcel 1717   class class class wbr 4154   ` cfv 5395  (class class class)co 6021   CCcc 8922   RRcr 8923   0cc0 8924   1c1 8925    + caddc 8927    x. cmul 8929    < clt 9054    <_ cle 9055   NNcn 9933   NN0cn0 10154   ^cexp 11310   !cfa 11494
This theorem is referenced by:  logfacubnd  20873
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-3 7  ax-mp 8  ax-gen 1552  ax-5 1563  ax-17 1623  ax-9 1661  ax-8 1682  ax-13 1719  ax-14 1721  ax-6 1736  ax-7 1741  ax-11 1753  ax-12 1939  ax-ext 2369  ax-sep 4272  ax-nul 4280  ax-pow 4319  ax-pr 4345  ax-un 4642  ax-cnex 8980  ax-resscn 8981  ax-1cn 8982  ax-icn 8983  ax-addcl 8984  ax-addrcl 8985  ax-mulcl 8986  ax-mulrcl 8987  ax-mulcom 8988  ax-addass 8989  ax-mulass 8990  ax-distr 8991  ax-i2m1 8992  ax-1ne0 8993  ax-1rid 8994  ax-rnegex 8995  ax-rrecex 8996  ax-cnre 8997  ax-pre-lttri 8998  ax-pre-lttrn 8999  ax-pre-ltadd 9000  ax-pre-mulgt0 9001
This theorem depends on definitions:  df-bi 178  df-or 360  df-an 361  df-3or 937  df-3an 938  df-tru 1325  df-ex 1548  df-nf 1551  df-sb 1656  df-eu 2243  df-mo 2244  df-clab 2375  df-cleq 2381  df-clel 2384  df-nfc 2513  df-ne 2553  df-nel 2554  df-ral 2655  df-rex 2656  df-reu 2657  df-rab 2659  df-v 2902  df-sbc 3106  df-csb 3196  df-dif 3267  df-un 3269  df-in 3271  df-ss 3278  df-pss 3280  df-nul 3573  df-if 3684  df-pw 3745  df-sn 3764  df-pr 3765  df-tp 3766  df-op 3767  df-uni 3959  df-iun 4038  df-br 4155  df-opab 4209  df-mpt 4210  df-tr 4245  df-eprel 4436  df-id 4440  df-po 4445  df-so 4446  df-fr 4483  df-we 4485  df-ord 4526  df-on 4527  df-lim 4528  df-suc 4529  df-om 4787  df-xp 4825  df-rel 4826  df-cnv 4827  df-co 4828  df-dm 4829  df-rn 4830  df-res 4831  df-ima 4832  df-iota 5359  df-fun 5397  df-fn 5398  df-f 5399  df-f1 5400  df-fo 5401  df-f1o 5402  df-fv 5403  df-ov 6024  df-oprab 6025  df-mpt2 6026  df-2nd 6290  df-riota 6486  df-recs 6570  df-rdg 6605  df-er 6842  df-en 7047  df-dom 7048  df-sdom 7049  df-pnf 9056  df-mnf 9057  df-xr 9058  df-ltxr 9059  df-le 9060  df-sub 9226  df-neg 9227  df-nn 9934  df-n0 10155  df-z 10216  df-uz 10422  df-seq 11252  df-exp 11311  df-fac 11495
  Copyright terms: Public domain W3C validator