A115539 Numbers k such that the concatenation of k with 5*k gives a square.

2040816326530612245, 8163265306122448980, 18367346938775510205, 265008112493239588967009194159005, 346133044889129259058950784207680, 438074634937804218496484586262845, 540832882639264467279610600324500

Offset

1,1

Links

Table of n, a(n) for n=1..7.

Example

2040816326530612245_10204081632653061225 = 14285714285714285715^2.

Crossrefs

Cf. A102567, A106497, A115527 - A115556.

Sequence in context: A113740 A281508 A281509 * A080129 A272519 A246234

Adjacent sequences: A115536 A115537 A115538 * A115540 A115541 A115542

Keyword

nonn,base

Author

Giovanni Resta, Jan 25 2006

Status

approved