1,5

For a given n there is more than one solution.

Table of n, a(n) for n=1..54.

a(5)=40 since 40*(40+5)*(40+5+5)=40*45*50=90000=300^2

Cf. A115878, A181646.

Sequence in context: A078084 A037937 A126652 * A117831 A152143 A277874

Adjacent sequences: A181640 A181641 A181642 * A181644 A181645 A181646

nonn

Carmine Suriano, Nov 03 2010, corrected Nov 10 2010

approved