2^(m-1)+3^n+5^(p+1)=11
2^m/2+3^n+5*5^p=11 (1)
2^m+3^n+5^p=7 (2)
(1)-(2)
-2^m/2+4*5^p=4
2^m=8(5^p-1)>0 5^p>1
2^m=8(5^p-1)代入(2)
3^n+9*5^p-8=7
3^n=15-9*5^p>0
5^p