A328089 Numbers k such that k+1 concatenated with k is a square.

81, 8241, 9801, 538276, 998001, 77837025, 99980001, 7922547264, 8643251344, 9223797609, 9999800001, 106710893289, 453378226756, 491023832064, 945958034529, 999998000001, 11916002265169, 15790977390244, 24917378001936, 25082758752025, 36315251812569

Offset: 1

Author

N. J. A. Sloane, Oct 17 2019

Keywords

• nonn
• base

References

• Luca, Florian, and Pantelimon Stănică. "Perfect Squares as Concatenation of Consecutive Integers." The American Mathematical Monthly 126.8 (2019): 728-734.

Crossrefs

A companion to A054214, A054215, A054216.