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A9275. Yet Another Number Sequence

编程题 普及/提高-

题目描述

Everyone knows what the Fibonacci sequence is. This sequence can be defined by the recurrence relation:

$F_{1}=1,F_{2}=2,F_{i}=F_{i-1}+F_{i-2} (i>2).$ We'll define a new number sequence $A_{i}(k)$ by the formula:

$A_{i}(k)=F_{i}×i^{k} (i>=1).$ In this problem, your task is to calculate the following sum: $A_{1}(k)+A_{2}(k)+...+A_{n}(k)$ . The answer can be very large, so print it modulo $1000000007$ $(10^{9}+7)$ .

输入格式

The first line contains two space-separated integers $n$ , $k$ $(1<=n<=10^{17}; 1<=k<=40)$ .

输出格式

Print a single integer — the sum of the first $n$ elements of the sequence $A_{i}(k)$ modulo $1000000007$ $(10^{9}+7)$ .

输入输出样例

输入 #1
1 1
输出 #1
1
输入 #2
4 1
输出 #2
34
输入 #3
5 2
输出 #3
316
输入 #4
7 4
输出 #4
73825
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