A115537 Numbers k such that the concatenation of 4*k with k gives a square.

17728531856, 27700831025, 39889196676, 54293628809, 70914127424, 89750692521, 32653061224489796, 73469387755102041, 1245674740484429065743944636678200692041522491349481

Offset

1,1

Links

Table of n, a(n) for n=1..9.

Example

70914127424_17728531856 = 84210526316^2.

Crossrefs

Cf. A102567, A106497, A115527 - A115556.

Sequence in context: A233799 A330278 A202724 * A233486 A270895 A273186

Adjacent sequences: A115534 A115535 A115536 * A115538 A115539 A115540

Keyword

nonn,base

Author

Giovanni Resta, Jan 25 2006

Status

approved