#P6597. 烯烃计数
烯烃计数
Background
You may need:
Since Luogu does not have the two problems above, this problem is made instead.
Problem Description
Find the number of isomers of alkenes (homologs of ethylene) with chemical formula .
In this problem, stereoisomerism and cis-trans isomerism are not considered.
The answer should be taken modulo .
Input Format
A positive integer .
Output Format
Output a total of lines, where the -th line is the answer for alkenes with carbon atoms.
5
1
1
3
5
Hint
Explanation for Sample 1
- : ethylene.
- : propylene.
- : 1-butene; 2-butene; 2-methyl-1-propene.
- : 1-pentene; 2-pentene; 2-methyl-1-butene; 3-methyl-1-butene; 2-methyl-2-butene.
Constraints
For of the testdata, it is guaranteed that .
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