A048412 a(n)^2 is a square whose consecutive digits differ by 1.

0, 1, 2, 3, 11, 26, 111, 1111, 11111, 111111, 1111111, 11111111, 111111111

Offset: 1

Author

Patrick De Geest, Apr 15 1999

Keywords

• nonn
• base
• more

Comments

a(14), if it exists, is > 10^17. - Lars Blomberg, Nov 25 2016

a(14), if it exists, is > 10^26. - Michael S. Branicky, Apr 22 2025

Crossrefs

Cf. A002477, A048411.

Formula

a(n) = sqrt(A048411(n)).

Extensions

Offset changed to 1 by Jinyuan Wang, Sep 04 2021