A145848 Squares with an even number of digits, where the first half is a square and the second half is a nonzero square.

49, 1681, 144400, 225625, 256036, 324900, 576081, 24019801, 1299602500, 1587624025, 2371690000, 2496401296, 2528178961, 2924105625, 3132976729, 5198410000, 5616902916, 6350496100, 8122515625, 9985605184, 249001998001

Offset

1,1

Links

Jon E. Schoenfield, Table of n, a(n) for n = 1..221

Four Puzzles for the Price of One - from the 1997 USSR math olympiad

Example

1681 is a square, where the first two digits form a square and the last two digits form a nonzero square.

Mathematica

Flatten[Table[ Select[Flatten[ Table[FromDigits[ Join[IntegerDigits[i^2], PadLeft[IntegerDigits[j^2], n]]], {i, Floor[Sqrt[10^(n - 1)]], Floor[Sqrt[10^n - 1]]}, {j, Floor[Sqrt[10^n - 1]]}]], IntegerQ[Sqrt[ # ]] &], {n, 5}]]

Crossrefs

Sequence in context: A088068 A140394 A008843 * A014942 A260856 A367378

Adjacent sequences: A145845 A145846 A145847 * A145849 A145850 A145851

Keyword

nonn,base

Author

Tanya Khovanova, Oct 21 2008

Extensions

More terms from Jon E. Schoenfield, Nov 17 2008

Edited by Charles R Greathouse IV, Aug 02 2010

Status

approved