May 17 answered Solving $x^{\log(x)}=\frac{x^3}{100}$ May 17 answered Simplify $\log_23\ \log_34\ \log_4 5\ \log_5 6\ \log_6 7\ \log_7 8$ May 13 awarded Teacher May 12 comment Find the longest subsequence of two stringsThis link might help you.. ics.uci.edu/~eppstein/161/960229.html May 12 answered Finding cycles in a graph May 12 answered Show that the matrix $A^2 + I$ is invertible for all matrices $A$, where $A$ is an $n \times n$ symmetric matrix. May 12 awarded Popular Question May 12 comment How prove this matrix $rank (A_{11}A_{12})=rank(A_{12})$What do you mean by $A_{11}A_{12}$? Submatrix multiplied or just the concatenation of cols? May 6 awarded Popular Question May 6 comment Permutation & Combination - how many numbers smaller than $2.10^8$ and are divisible by $3$ can be written by means of the digits $0$,$1$ and $2$Total number of numbers divisible by $3$ is $2.10^8/3$. Now we need to count only the numbers whose digit are $0,1,2$ May 5 awarded Yearling May 5 awarded Yearling Apr 27 awarded Notable Question Apr 24 awarded Supporter Apr 24 comment How to determine Center of Gravity?intuition is enuough Apr 24 asked How to determine Center of Gravity? Apr 22 awarded Yearling Apr 22 awarded Yearling Apr 6 asked How to print frequency k words from more than 1TB of data? Apr 4 comment Strings of same length to graph structureim not asking for solution. Need to know which data structure to use?