Register
Login
Username
Password
Login
forgot your password?
Home
Forum
+0
Formulary
Maths
Help
Complex Numbers
Integral Calculus
Differential Calculus
Equations
Graphs
Linear Algebra
Number theory
Percent
Standard Functions
Statistics
Trigonometry
Unit Conversion
Units
About
Imprint
Privacy Policy
Terms of Service
Credits
Google+
Facebook
Contact Email
ruiruima
Username
ruiruima
Score
17
Membership
Stats
Questions
3
Answers
0
3 Questions
0 Answers
+1
34
1
+17
Number theory
How many positive integers are not less than the sum of their divisors?
●
ruiruima
Jan 14, 2024
+2
31
1
+17
Ordered pairs of primes
How many ordered pairs of primes (a,b) satisfy a+b=22?
●
ruiruima
Jan 13, 2024
+2
33
1
+17
Arithmetic sequence
The 80th term of an arithmetic sequence is twice the 30th term. If the first term of the sequence is 7, what is the 40th term?
ElectricPavlov
●
ruiruima
Jan 12, 2024