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Expression of type Lambda

from the theory of proveit.numbers.exponentiation

In [1]:
import proveit
# Automation is not needed when building an expression:
proveit.defaults.automation = False # This will speed things up.
proveit.defaults.inline_pngs = False # Makes files smaller.
%load_expr # Load the stored expression as 'stored_expr'
# import Expression classes needed to build the expression
from proveit import Conditional, Lambda, n, x
from proveit.logic import Equals, InSet
from proveit.numbers import Exp, Mult, Natural, Neg, two
In [2]:
# build up the expression from sub-expressions
sub_expr1 = Mult(two, n)
expr = Lambda(n, Conditional(Equals(Exp(Neg(x), sub_expr1), Exp(x, sub_expr1)), InSet(n, Natural)))
expr:
In [3]:
# check that the built expression is the same as the stored expression
assert expr == stored_expr
assert expr._style_id == stored_expr._style_id
print("Passed sanity check: expr matches stored_expr")
Passed sanity check: expr matches stored_expr
In [4]:
# Show the LaTeX representation of the expression for convenience if you need it.
print(stored_expr.latex())
n \mapsto \left\{\left(-x\right)^{2 \cdot n} = x^{2 \cdot n} \textrm{ if } n \in \mathbb{N}\right..
In [5]:
stored_expr.style_options()
no style options
In [6]:
# display the expression information
stored_expr.expr_info()
 core typesub-expressionsexpression
0Lambdaparameter: 23
body: 2
1ExprTuple23
2Conditionalvalue: 3
condition: 4
3Operationoperator: 5
operands: 6
4Operationoperator: 7
operands: 8
5Literal
6ExprTuple9, 10
7Literal
8ExprTuple23, 11
9Operationoperator: 13
operands: 12
10Operationoperator: 13
operands: 14
11Literal
12ExprTuple15, 16
13Literal
14ExprTuple21, 16
15Operationoperator: 17
operand: 21
16Operationoperator: 19
operands: 20
17Literal
18ExprTuple21
19Literal
20ExprTuple22, 23
21Variable
22Literal
23Variable