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A353080
Numbers whose squares have the first three digits the same as the next three digits.
2
1429, 1537, 1692, 1823, 2001, 2312, 2467, 2729, 2858, 3148, 3242, 3635, 3849, 4002, 4541, 4552, 5851, 6003, 6216, 6296, 6375, 7145, 7152, 7159, 7698, 8004, 9093, 9104, 9235, 9444, 10005, 10154, 12006, 12335, 13645, 14007, 14290, 14325, 15272, 15370, 16008, 16531
OFFSET
1,1
LINKS
EXAMPLE
1429^2 = 2042041 and 1537^2 = 2362369. Thus, 1429 and 1537 are both in this sequence.
MAPLE
q:= n-> (s-> is(s[1..3]=s[4..6]))(""||(n^2)):
select(q, [$317..17000])[]; # Alois P. Heinz, Apr 22 2022
MATHEMATICA
Select[Range[317, 20000], Take[IntegerDigits[#^2], {1, 3}] == Take[IntegerDigits[#^2], {4, 6}] &]
PROG
(Python)
def ok(n): s = str(n**2); return len(s) > 5 and s[:3] == s[3:6]
print([k for k in range(20000) if ok(k)]) # Michael S. Branicky, Apr 22 2022
CROSSREFS
Sequence in context: A292704 A321036 A094230 * A238136 A060364 A243834
KEYWORD
nonn,base
AUTHOR
Tanya Khovanova, Apr 22 2022
STATUS
approved