672400

Appears in sequences

• Squares of even triangular numbers.at n=19A014738
• Squares which are palindromes in base 9.at n=10A029995
• Squares which repeat with at least two full periods when written in base 2.at n=5A071128
• Squares which repeat with at least two full periods when written in base 4.at n=2A071130
• a(n) = x^2 = A090116(n)^2 is the least square that is "surrounded" by two closest primes, by prevprime(x^2) and nextprime(x^2) whose difference nextprime - prevprime = 2n.at n=29A090117
• Numbers k with the property that it is possible to write the base 2 expansion of k as concat(a_2,b_2), with a_2>0 and b_2>0 such that, converting a_2 and b_2 to base 10 as a and b, we have (a+b)^2 = k.at n=28A258844
• Base-9 representation of a(n) is the concatenation of the base-9 representations of 1, 2, ..., n, n-1, ..., 1.at n=4A260859
• Number of (n+2) X (2+2) 0..1 arrays with each row and column divisible by 5, read as a binary number with top and left being the most significant bits.at n=9A262268
• Number of irreducible, unrooted, unoriented self-avoiding chains of length n for the square lattice.at n=16A334325
• a(n) = sigma_2(n)^2.at n=26A356533