$2^2$ has 3 factors and $3^2$ has 3 factors product 36 has 9 factors . Let us check if smaller square has 16 has 5 and 25 has 3 . So 36 is the smallest perfect square number having perfect square number of positive factors
some short and selected math problems of different levels in random order I try to keep the ans simple
Thursday, April 2, 2026
2026/028) Let n be a positive integer such that $12n^2+12n+11$ is a 4-digit number with all 4 digits equal. Determine the value of n.
Let it be 1111x . Add 1 in both sides to get
$12n^2 + 12n + 12 = 1111x + 1$
Work mod 12 to get
$7x + 1 = 0 \pmod {12}$
So x is odd
Trying x odd values that is $1,3,5,9,11$ we get x is 5 .
So $12n^2 + 12n + 12 = 5556$
Or $n^2 + n + 1 = 463$
Or $n = 21$
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