A181643 a(n) is the smallest value such that a(n)*[a(n)+n]*[a(n)+n+n]=y^2 is a perfect square

0, 0, 0, 0, 40, 6, 18, 0, 0, 0, 0, 0, 0, 4, 10, 0, 0, 0, 0, 5, 7, 0, 0, 1, 0, 0, 0, 72, 0, 15, 0, 0, 0, 128, 0, 0, 0, 0, 936, 0, 800, 0, 0, 0, 360, 196, 0, 0, 0, 0, 0, 0, 0, 54

Offset

1,5

Comments

For a given n there is more than one solution.

Links

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

Example

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

Crossrefs

Cf. A115878, A181646.

Sequence in context: A078084 A037937 A126652 * A117831 A152143 A277874

Adjacent sequences: A181640 A181641 A181642 * A181644 A181645 A181646

Keyword

nonn

Author

Carmine Suriano, Nov 03 2010, corrected Nov 10 2010

Status

approved