OFFSET
1,1
REFERENCES
R. Ondrejka, Problem 1130: Biperiod Squares, Journal of Recreational Mathematics, Vol. 14:4 (1981-82), 299. Solution by F. H. Kierstead, Jr., JRM, Vol. 15:4 (1982-83), 311-312.
LINKS
Chai Wah Wu, Table of n, a(n) for n = 1..34
PROG
(Python)
from itertools import count, islice
from sympy import sqrt_mod
def A181790_gen(): # generator of terms
for j in count(9):
b = 10**j
a = b*10+1
for k in sorted(sqrt_mod(0, a, all_roots=True)):
if a*b <= k**2 < a*(a-1) and len(set(str(m:=k**2//a))) == 10:
yield m
CROSSREFS
KEYWORD
nonn,base
AUTHOR
William Rex Marshall, Nov 12 2010
STATUS
approved