Hi I have the following code
\documentclass[12pt,a4paper,twoside]{report}
\setlength{\textwidth}{16cm}
\setlength{\oddsidemargin}{0pt}
\setlength{\evensidemargin}{0pt}
\setlength{\parskip}{3mm}
\setlength{\parindent}{0mm}
\usepackage{amsmath,amsthm,tabu}
\usepackage{tabularx,ragged2e,booktabs,caption}
\usepackage{mathtools}
\begin{document}
\begin{tabularx}{\textwidth}{|c|>{\raggedright\arraybackslash}X |>{\raggedright\arraybackslash}X|c|c|}
\hline
$n$ & $B_n$ & $w_n$ & $w_n\pmod{5}$ \\
\hline
1 & $-2^2\cdot3^6$ & $1$ & 1\\
\hline
2 & $2^2\cdot3^4$ & $1$ & 1\\
\hline
3 & $-2^2\cdot3^6$ & $1$ & 1 \\
\hline
4 & $2^2\cdot3^4\cdot19^2$ & $19$ & -1 \\
\hline
5 & $2^2\cdot3^6\cdot13^2$ & $13$ & -2 \\
\hline
6 & $3^4\cdot127^2$ & $127$ & 2 \\
\hline
7 & $-2^2\cdot3^6\cdot1291^2$ & $1291$ & 1\\
\hline
8 & $2^2\cdot14741^2$ & $14741$ & 1\\
\hline
9 & $-2^2\cdot3^6\cdot7901^2$ & $7901$ & 1 \\
\hline
10 & $2^2\cdot3^4\cdot3156697^2$ & $3156697$ & 2 \\
\hline
11 & $-2^2\cdot3^6\cdot 47^2\cdot799817^2$ & $ 47\cdot799817$ & -1 \\
\hline
12 & $3^4\cdot19^2\cdot6490213^2$ & $19\cdot6490213$ & 2 \\
\hline
13 & $-2^2\cdot3^6\cdot149^2\cdot239^2\cdot753611^2$ & $149\cdot239\cdot753611$ & 1 \\
\hline
14 & $2^2\cdot3^4\cdot53^2\cdot58963203163^2$ & $53\cdot58963203163$ & -1 \\
\hline
15 & $-2^2\cdot3^6\cdot13^2\cdot1361^2\cdot1277496791^2$ & $13\cdot1361\cdot1277496791$ & -2 \\
\hline
16 & $2^2\cdot1326053^2\cdot2774248223^2$ & $1326053\cdot2774248223$ & -1 \\
\hline
17 & $-2^2\cdot3^6\cdot557^2\cdot3331^2\cdot5147^2\cdot108649481^2$ & $557\cdot3331\cdot5147\cdot108649481$ & -1 \\
\hline
18 & $3^4\cdot127^2\cdot271^2\cdot359^2\cdot11283039459271^2$ & $127\cdot271\cdot359\cdot11283039459271$ & -2 \\
\hline
19 & $-2^2\cdot3^6\cdot157^2\cdot190367^2\cdot417192073484831^2$ & $157\cdot190367\cdot417192073484831$ & -1 \\
\hline
20 & $19^2\cdot67^2\cdot251^2\cdot17327^2\cdot870931^2\cdot2201234507^2$ & $19\cdot67\cdot251\cdot17327\cdot870931\cdot 2201234507$ & 2 \\
\hline
21 & $-2^2\cdot3^6\cdot1279^2\cdot1291^2\cdot173549^2\cdot1505227^ 2\cdot 1826825317^2$ & $1279\cdot1291\cdot173549\cdot1505227\cdot 1826825317$ & -1 \\
\hline
22 & $2^2\cdot3^4\cdot77239^2\cdot1477946658973^2\cdot18191777262077^2$ & $77239\cdot1477946658973\cdot18191777262077$ & -1 \\
\hline
23 & $-2^2\cdot3^6\cdot2053^2\cdot240257^2\cdot664708181^2\cdot 531369737672759^2$ & $2053\cdot240257\cdot664708181\cdot 531369737672759$ & -1 \\
\hline
24 & $8389^2\cdot14741^2\cdot51683576785065855501\allowbreak80202343^2$ & $8389\cdot14741\cdot51683576785065855501\allowbreak80202343$ & 2\\
\hline
25 & $-2^2 \cdot 3^6 \cdot13^2\cdot103^2\cdot643355871684956977670141294665607837^2$ & $13\cdot103\cdot643355871684956977670141294665607837$ & -2 \\
\hline
26 & $2^2\cdot3^4\cdot30347^2\cdot49857737^2\cdot357534917849299^2 \cdot1706574816319801^2$ & $30347\cdot49857737\cdot357534917849299\cdot1706574816319801$ & 1 \\
\hline
27 & $-2^2\cdot3^6\cdot659^2\cdot1543^2\cdot7901^2\cdot5808403^2\cdot158844137^2\cdot 1158342511^2 \cdot50827475227^2$ & $659\cdot1543\cdot7901\cdot 5808403\cdot 158844137\cdot 1158342511\cdot50827475227$ & -1 \\
\hline
28 & $2^2 \cdot3^4\cdot19^2 \cdot987143^2\cdot635616634615737191007756403110436513428793^2$ & $19\cdot 987143\cdot635616634615737191007756403110436513428793$ & 1 \\
\hline
29 & $-2^2 \cdot3^6\cdot1073602478183^2 \cdot18489706532449215619546038681792311392837^2$ & $1073602478183\cdot 18489706532449215619546038681792311392837$ & 1 \\
\hline
30 & $3^4\cdot127^2\cdot6173^2\cdot80831^2\cdot224969^2\cdot3156697^2\cdot 5489411^2\cdot 60570921936790713413493767^2$ & $127\cdot 6173\cdot 80831\cdot 224969\cdot 3156697\cdot 5489411\cdot 60570921936790713413493767$ & 1 \\
\hline
\end{tabularx}
\end{document}
The problem occurred at n=25,28,29 where the numbers in the second and third column are too long to fit in one column. Is there a way to make it nicely remain in the same column without overlapping with other columns.


:)– Fran Apr 13 '16 at 09:46sidewaysenvironment might be employed in an answer. – Mico Apr 13 '16 at 10:59