For the natural number 1,2,3,..., n has 1 & sup3; + 2 & sup3; + 3 & sup3; +... + n & sup3; = [n (n + 1) / 2] & sup2;, that is 1 & sup3; + 2 & sup3+ For this equation, we propose a question, if the sequence {an}, has an > 0, and satisfies the equation (A1 & sup3; + A2 & sup3; +. + an & sup3;) = (a1 + A2 + a3 +.. + an) & sup2;, is an = n tenable? If it is tenable, prove it; otherwise, give a counter example

For the natural number 1,2,3,..., n has 1 & sup3; + 2 & sup3; + 3 & sup3; +... + n & sup3; = [n (n + 1) / 2] & sup2;, that is 1 & sup3; + 2 & sup3+ For this equation, we propose a question, if the sequence {an}, has an > 0, and satisfies the equation (A1 & sup3; + A2 & sup3; +. + an & sup3;) = (a1 + A2 + a3 +.. + an) & sup2;, is an = n tenable? If it is tenable, prove it; otherwise, give a counter example

It is proved that: SN = a1 + A2 + a3 +.. + an; from the question: (A1 & sup3; + A2 & sup3; +. + an & sup3;) = (SN) & sup2; (A1 & sup3; + A2 & sup3; +. + an-1 & sup3;) = (sn-1) & sup2; (Sn + sn-1) = an & sup3;, that is, (Sn + sn-1) an = an & S