A052212 Numbers k whose square contains the digits of k in order (but not necessarily consecutively).

1, 5, 6, 10, 11, 25, 50, 60, 76, 95, 96, 100, 101, 105, 110, 125, 205, 250, 305, 371, 376, 405, 441, 500, 501, 505, 506, 525, 600, 601, 605, 625, 676, 705, 756, 760, 805, 825, 826, 905, 946, 950, 960, 976, 995, 996, 1000, 1001, 1005, 1006, 1010, 1011, 1021

Offset: 1

Author

Erich Friedman, Jan 29 2000

Keywords

• base
• easy
• nonn

Comments

Subsequence of A046829. - R. J. Mathar, Oct 13 2008

Examples

			1276^2 = 1628176, which contains the digits 1,2,7,6 in that order.
		

Programs

Python

from itertools import count, islice
def A052212_gen(startvalue=1): # generator of terms >= startvalue
    for k in count(max(startvalue,1)):
        c = iter(str(k**2))
        if all(map(lambda b:any(map(lambda a:a==b,c)),str(k))):
            yield k
A052212_list = list(islice(A052212_gen(),20)) # Chai Wah Wu, Apr 03 2023

Extensions

Definition clarified by N. J. A. Sloane, Apr 04 2023