540225

Appears in sequences

• Expansion of e.g.f. theta_3^(7/2).at n=8A015667
• Squares containing 2k digits in which the sum of the first k digits = that of the rest.at n=23A068897
• Squares which repeat with at least two full periods when written in base 3.at n=8A071129
• Solutions to mod(sigma(x), 6) = 5.at n=17A074384
• Numbers k having exactly one divisor d such that in binary representation d and k/d have the same number of 1's as k.at n=28A080026
• Coefficients of power series A(x) consist entirely of squares, where A(x) = A083352(x)^2 + A083352(x) - 1.at n=35A083353
• Records in A160256.at n=39A151545
• Odd abundant numbers whose abundance is odd.at n=5A156942
• Squares that are the concatenation of two Pythagorean integers a and b with a^2 + b^2 = c^2 (a and b are without any left-hand zeros).at n=4A257650
• Magic sums of 3 X 3 semimagic squares of squares whose rows, columns, and at least one of the two main diagonals sum to the same number.at n=5A271021
• Numbers n such that the product of n and the sum of the reciprocal of their anti-divisors is an integer.at n=30A272890
• Odd abundant numbers k for which sigma(k) == 3 (mod 4).at n=3A325311
• a(n) is the largest odd positive integer that is abundant and has the same prime signature as A279537(n) or 0 if no such integer exists.at n=52A343330
• Odd numbers k such that sigma(k) > 2*k and A003415(sigma(k)) < k, where A003415 is the arithmetic derivative, and sigma is the sum of divisors function.at n=1A347890
• Squares whose base-3 expansion has no 2.at n=44A363408