324900

Appears in sequences

• Squares which are the concatenation of two nonzero squares.at n=22A039686
• Squares containing 2k digits in which the sum of the first k digits = that of the rest.at n=14A068897
• Square associated with twin primes (p,p+2): p(p+2) + 1. Square of the average of twin primes.at n=25A075369
• Numbers k such that the sets of prime factors (ignoring multiplicity) of A000203(k) = sigma(k) and of A001157(k) = sigma_2(k) are identical.at n=12A081380
• Square numbers which equal a triangular number times an odd number between 1 and 15.at n=15A094973
• a(1)=1; at n>=2, a(n) = least square > a(n-1) such that sum a(1)+...+a(n) is a prime number.at n=27A139033
• Squares with an even number of digits, where the first half is a square and the second half is a nonzero square.at n=5A145848
• Squares which are concatenation of two positive squares with possible intervening zeros.at n=25A147608
• Numbers with prime factorization p^2*q^2*r^2*s^2 where p, q, r, and s are distinct primes.at n=6A190377
• Number of 0..n arrays x(0..6) of 7 elements with zero 6th difference.at n=12A200158
• Number of n X 4 0..1 arrays avoiding 0 0 0 and 1 1 1 horizontally and 0 0 1 and 0 1 1 vertically.at n=29A208065
• Number of n X 4 0..1 arrays avoiding 0 0 1 and 0 1 1 horizontally and 0 0 1 and 1 0 1 vertically.at n=18A208138
• Composite numbers whose number of proper divisors has a number of proper divisors which has a prime number of proper divisors.at n=12A223457
• Squares, without multiplicity, that are the concatenation of two integers (without leading zeros) the product of which is also a square.at n=23A258060
• Number of nX4 0..4 arrays with every repeated value in every row and column greater than the previous repeated value.at n=1A268203
• T(n,k)=Number of nXk 0..k arrays with every repeated value in every row and column greater than the previous repeated value.at n=11A268204
• Number of 2Xn 0..n arrays with every repeated value in every row and column greater than the previous repeated value.at n=3A268206
• Number of nX4 0..4 arrays with every repeated value in every row greater than, and every column greater than or equal to, the previous repeated value.at n=1A268248
• T(n,k)=Number of nXk 0..k arrays with every repeated value in every row greater than, and every column greater than or equal to, the previous repeated value.at n=11A268249
• Numbers n such that the product of n and the sum of the reciprocal of their anti-divisors is an integer.at n=26A272890