Expression 3: "P" Subscript, "r" "i" "m" "e" "C" "o" "u" "n" "t" , Baseline left parenthesis, "x" , right parenthesis equals Start sum from "j" equals 2 to floor left parenthesis, "x" , right parenthesis , end sum, left brace, Start sum from "i" equals 2 to StartRoot, "j" , EndRoot , end sum, left parenthesis, 1 minus left brace, mod left parenthesis, "j" , "i" , right parenthesis greater than 0 , 0 , right brace , right parenthesis equals 0 , 0 , right bracePrimeCountx=floorx∑j=2j∑i=21−modj,i>0,0=0,0
3
Expression 4: "y" equals Start sum from "n" equals 1 to 250, end sum, StartFraction, 1 Over "n" , EndFraction "P" Subscript, "r" "i" "m" "e" "C" "o" "u" "n" "t" , Baseline left parenthesis, "x" Superscript, StartFraction, 1 Over "n" , EndFraction , Baseline , right parenthesisy=250∑n=11nPrimeCountx1n
4
Expression 5: Start sum from "n" equals 1 to floor left parenthesis, log Subscript, 2 , Baseline left parenthesis, "x" , right parenthesis , right parenthesis , end sum, StartFraction, "P" Subscript, "r" "i" "m" "e" "C" "o" "u" "n" "t" , Baseline left parenthesis, "x" Superscript, StartNestedFraction, 1 NestedOver "n" , EndNestedFraction , Baseline , right parenthesis Over "n" , EndFractionfloorlog2x∑n=1PrimeCountx1nn