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

Author

Amarnath Murthy, Apr 28 2001

Keywords

• nonn
• base

Examples

			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.

Extensions

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

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