#pragma GCC optimize("Ofast")
#pragma GCC target("avx2")

#define rd_init() char*rp=({char*mmap();mmap(0l,1l<<25,1,2,0,0ll);})
#define rd() ({long _v=0,_c;while(_c=*rp++-48,_c>=0)_v=_v*10+_c;_v;})
#define WTHI(v) {unsigned _z=v,_n=0;ulong _d=0;while(++_n,_d=_d<<8|0x30|_z%10,_z/=10);*(ulong*)wp=_d;wp+=_n;}
#define WTLO(v) {unsigned _z=v,_n=8;ulong _d=0;while(_d=_d<<8|0x30|_z%10,_z/=10,--_n);*(ulong*)wp=_d;wp+=8;}
#define wt(v) if(v>=100000000){WTHI(v/100000000);WTLO(v);}else{WTHI(v);}
#define rep3(v,s,e) for(typeof(e) v=s;v<e;++v)
#define MD 998244353

typedef unsigned long ulong;

char wbuf[1<<25];

int main(){
	rd_init();
	char*wp=wbuf;
	for(int t=rd();t--;){
		unsigned n=rd();
		int k=rd();
		ulong z=0;
		rep3(i,2,k+2){
			ulong y=1;
			ulong a=i;
			for(unsigned j=n;j;j>>=1){
				if(j&1){
					y=y*a%MD;
				}
				a=a*a%MD;
			}
			z+=y;
		}
		z%=MD;
		wt(z);
		*wp++='\n';
	}
	write(1,wbuf,wp-wbuf);
	_exit(0);
}