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

1,2

Links

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

Sean A. Irvine, Java program (github)

Example

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

Crossrefs

Cf. A050634, A050635.

Sequence in context: A107906 A328127 A323385 * A330150 A340586 A005445

Adjacent sequences: A061356 A061357 A061358 * A061360 A061361 A061362

Keyword

nonn,base

Author

Amarnath Murthy, Apr 28 2001

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

Status

approved