Users' Mathboxes Mathbox for Thierry Arnoux < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >   Mathboxes  >  df-fib Structured version   Visualization version   Unicode version

Definition df-fib 30459
Description: Define the Fibonacci sequence, where that each element is the sum of the two preceding ones, starting from 0 and 1. (Contributed by Thierry Arnoux, 25-Apr-2019.)
Assertion
Ref Expression
df-fib  |- Fibci  =  (
<" 0 1 ">seqstr ( w  e.  (Word 
NN0  i^i  ( `' #
" ( ZZ>= `  2
) ) )  |->  ( ( w `  (
( # `  w )  -  2 ) )  +  ( w `  ( ( # `  w
)  -  1 ) ) ) ) )

Detailed syntax breakdown of Definition df-fib
StepHypRef Expression
1 cfib 30458 . 2  class Fibci
2 cc0 9936 . . . 4  class  0
3 c1 9937 . . . 4  class  1
42, 3cs2 13586 . . 3  class  <" 0
1 ">
5 vw . . . 4  setvar  w
6 cn0 11292 . . . . . 6  class  NN0
76cword 13291 . . . . 5  class Word  NN0
8 chash 13117 . . . . . . 7  class  #
98ccnv 5113 . . . . . 6  class  `' #
10 c2 11070 . . . . . . 7  class  2
11 cuz 11687 . . . . . . 7  class  ZZ>=
1210, 11cfv 5888 . . . . . 6  class  ( ZZ>= ` 
2 )
139, 12cima 5117 . . . . 5  class  ( `' # " ( ZZ>= `  2
) )
147, 13cin 3573 . . . 4  class  (Word  NN0  i^i  ( `' # " ( ZZ>=
`  2 ) ) )
155cv 1482 . . . . . . . 8  class  w
1615, 8cfv 5888 . . . . . . 7  class  ( # `  w )
17 cmin 10266 . . . . . . 7  class  -
1816, 10, 17co 6650 . . . . . 6  class  ( (
# `  w )  -  2 )
1918, 15cfv 5888 . . . . 5  class  ( w `
 ( ( # `  w )  -  2 ) )
2016, 3, 17co 6650 . . . . . 6  class  ( (
# `  w )  -  1 )
2120, 15cfv 5888 . . . . 5  class  ( w `
 ( ( # `  w )  -  1 ) )
22 caddc 9939 . . . . 5  class  +
2319, 21, 22co 6650 . . . 4  class  ( ( w `  ( (
# `  w )  -  2 ) )  +  ( w `  ( ( # `  w
)  -  1 ) ) )
245, 14, 23cmpt 4729 . . 3  class  ( w  e.  (Word  NN0  i^i  ( `' # " ( ZZ>= ` 
2 ) ) ) 
|->  ( ( w `  ( ( # `  w
)  -  2 ) )  +  ( w `
 ( ( # `  w )  -  1 ) ) ) )
25 csseq 30445 . . 3  class seqstr
264, 24, 25co 6650 . 2  class  ( <" 0 1 ">seqstr ( w  e.  (Word 
NN0  i^i  ( `' #
" ( ZZ>= `  2
) ) )  |->  ( ( w `  (
( # `  w )  -  2 ) )  +  ( w `  ( ( # `  w
)  -  1 ) ) ) ) )
271, 26wceq 1483 1  wff Fibci  =  (
<" 0 1 ">seqstr ( w  e.  (Word 
NN0  i^i  ( `' #
" ( ZZ>= `  2
) ) )  |->  ( ( w `  (
( # `  w )  -  2 ) )  +  ( w `  ( ( # `  w
)  -  1 ) ) ) ) )
Colors of variables: wff setvar class
This definition is referenced by:  fib0  30461  fib1  30462  fibp1  30463
  Copyright terms: Public domain W3C validator