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A060812
Numbers whose square has a majority of one digit and does not end in 0.
1
1, 2, 3, 11, 12, 15, 21, 22, 26, 38, 109, 119, 131, 149, 165, 168, 173, 212, 216, 235, 258, 264, 298, 313, 738, 745, 1001, 1002, 1003, 1022, 1054, 1056, 1059, 1156, 1202, 1291, 1346, 1378, 1414, 1415, 1454, 1484, 1485, 1515, 1585, 1609, 1633, 1665, 1668
OFFSET
1,2
COMMENTS
If 10^d < k < 10^d + 10^floor((2*d-3)/6), then k^2 has a majority of digits 0. In particular, the sequence is infinite. Robert Israel, Dec 20 2023
LINKS
EXAMPLE
2038^2 = 4153444 and more than half the digits are 4's.
MAPLE
filter:= proc(n) local s, t, d;
if n mod 10 = 0 then return false fi;
s:= sort(convert(n^2, base, 10));
d:= nops(s);
t:= s[ceil(d/2)];
numboccur(t, s) > d/2;
end proc:
select(filter, [$1..2000]); # Robert Israel, Dec 20 2023
CROSSREFS
Sequence in context: A189818 A116032 A116029 * A212129 A172409 A062936
KEYWORD
base,easy,nonn
AUTHOR
Erich Friedman, Apr 29 2001
STATUS
approved