Common expressions for the theory of proveit.numbers.summation

import proveit
# Prepare this notebook for defining the common expressions of a theory:
%common_expressions_notebook # Keep this at the top following 'import proveit'.
from proveit import Function
from proveit import a, b, f, l, k, Q
from proveit.core_expr_types import b_1_to_j
from proveit.numbers import Sum

%begin common

Defining common sub-expressions for theory 'proveit.numbers.summation'
Subsequent end-of-cell assignments will define common sub-expressions
%end_common will finalize the definitions

ak = Function(a, k)

ak:

al = Function(a, l)

al:

bk = Function(b, k)

bk:

bl = Function(b, l)

bl:

summation_b1toj_fQ = Sum(b_1_to_j, 
                         Function(f, b_1_to_j), 
                         condition=Function(Q, b_1_to_j))

summation_b1toj_fQ:

%end common

These common expressions may now be imported from the theory package: proveit.numbers.summation