A061363 a(1) = 9; a(n) = least number such that the concatenation a(n)a(n-1)...a(2)a(1) is a square.

9, 4, 18, 167, 2401, 4086461727, 14079962896835441528, 309880704108832516500624685064706000856, 4681896102766617737298881383797502847166028831212571921983062786215145771871779

Offset

1,1

Links

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

Example

a(3)a(2)a(1) = 1849 = 43^2, a(4)a(3)a(2)a(1) = 1671849 = 1293^2.

Crossrefs

Cf. A050638, A050639, A061359, A061361.

Sequence in context: A248310 A133597 A075066 * A100077 A317739 A174679

Adjacent sequences: A061360 A061361 A061362 * A061364 A061365 A061366

Keyword

nonn,base

Author

Amarnath Murthy, Apr 28 2001

Extensions

Corrected by Larry Reeves (larryr(AT)acm.org), May 07 2001

More terms from Ulrich Schimke (ulrschimke(AT)aol.com), Nov 06 2001

Status

approved