Find 100 consecutive natural numbers, each of which is composite

So this is the sort of quesition where you will spend a while thinking about it, probably feel a little silly you haven't gotten it yet, then go "aha!", write down the answer and move on. It's all about spotting the trick.
Here the trick is to consider 101!, this is a number that is divisible by 2,3,...,100,101. So our list of 100 consecutive numbers is:
101! + 2,101! +3,...101!+100,101!+101
This works as each 101! + k is divisible by k as 101! and k both are.

GV
Answered by Gabriel V. STEP tutor

1445 Views

See similar STEP University tutors

Related STEP University answers

All answers ▸

Let p and q be different primes greater than 2. Prove that pq can be written as difference of two squares in exactly two different ways.


What do integrals and derivatives actually do/mean?


Let y=arcsin(x)/sqrt(1-x^2). Show that (1-x^2) y'-xy-1=0, and prove that, for all integers n>=0, (1-x^2)y^{n+2}-(2n+3)xy^{n+1} -(n+1)^2 y^{n}=0. (Superscripts denote repeated differentiation)


Suppose that 3=2/x(1)=x(1)+(2/x(2))=x(2)+(2/x(3))=x(3)+(2/x(4))+...Guess an expression, in terms of n, for x(n). Then, by induction or otherwise, prove the correctness of your guess.


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2026 by IXL Learning