codeforces#P1673C. Palindrome Basis
Palindrome Basis
Description
You are given a positive integer $n$. Let's call some positive integer $a$ without leading zeroes palindromic if it remains the same after reversing the order of its digits. Find the number of distinct ways to express $n$ as a sum of positive palindromic integers. Two ways are considered different if the frequency of at least one palindromic integer is different in them. For example, $5=4+1$ and $5=3+1+1$ are considered different but $5=3+1+1$ and $5=1+3+1$ are considered the same.
Formally, you need to find the number of distinct multisets of positive palindromic integers the sum of which is equal to $n$.
Since the answer can be quite large, print it modulo $10^9+7$.
The first line of input contains a single integer $t$ ($1\leq t\leq 10^4$) denoting the number of testcases.
Each testcase contains a single line of input containing a single integer $n$ ($1\leq n\leq 4\cdot 10^4$) — the required sum of palindromic integers.
For each testcase, print a single integer denoting the required answer modulo $10^9+7$.
Input
The first line of input contains a single integer $t$ ($1\leq t\leq 10^4$) denoting the number of testcases.
Each testcase contains a single line of input containing a single integer $n$ ($1\leq n\leq 4\cdot 10^4$) — the required sum of palindromic integers.
Output
For each testcase, print a single integer denoting the required answer modulo $10^9+7$.
Samples
2
5
12
7
74
Note
For the first testcase, there are $7$ ways to partition $5$ as a sum of positive palindromic integers:
- $5=1+1+1+1+1$
- $5=1+1+1+2$
- $5=1+2+2$
- $5=1+1+3$
- $5=2+3$
- $5=1+4$
- $5=5$
For the second testcase, there are total $77$ ways to partition $12$ as a sum of positive integers but among them, the partitions $12=2+10$, $12=1+1+10$ and $12=12$ are not valid partitions of $12$ as a sum of positive palindromic integers because $10$ and $12$ are not palindromic. So, there are $74$ ways to partition $12$ as a sum of positive palindromic integers.