A061359 a(1) = 1; a(n) = least number such that the concatenation a(n)a(n-1)...a(2)a(1) is a square.

1, 8, 16, 146, 22086, 31071113326, 365107058344463715696, 2684967738644586785227227090233956040549004, 809079884187716191997158821357206898310718837487307207657194711477350102495950972665

Offset: 1

Author

Amarnath Murthy, Apr 28 2001

Keywords

• nonn
• base

Examples

			a(3)a(2)a(1) = 1681 = 41^2, a(4)a(3)a(2)a(1) = 1461681 = 1209^2.
		

Links

• Sean A. Irvine, Java program (github)

Crossrefs

Cf. A050634, A050635.

Extensions

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

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