405769

Appears in sequences

• Squares with internal digits also forming a square > 0.at n=23A069701
• Numbers whose digital sum is equal to the sum of primes from their smallest to largest prime factor.at n=35A076406
• Squares whose internal digits form a square.at n=39A077355
• Squares whose external digits (MSD and LSD) as well as internal digits form squares.at n=15A077357
• Largest n-digit square whose external digits as well as internal digits form a square, or 0 if no such number exists.at n=5A077364
• 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=25A080026
• Squares that are the sum of 3 consecutive primes.at n=20A080665
• a(n) = (15*n^4 + 22*n^3 + 45*n^2 + 14*n) / 24.at n=28A101166
• Numbers of the form (7^i)*(13^j).at n=23A108056
• A modified Heron sequence starting from 1, 2.at n=11A134588
• Positive numbers y such that y^2 is of the form x^2+(x+2401)^2 with integer x.at n=31A157247
• Numbers whose sum of proper square divisors is a palindrome in base 10 having at least two digits.at n=29A232892
• Fixed points of A153212: After a(1) = 1, numbers of the form p_i1^i1 * p_i2^(i2-i1) * p_i3^(i3-i2) * ... * p_ik^(ik-i_{k-1}), where p_i's are distinct primes present in the prime factorization of n, with i1 < i2 < i3 < ... < ik, and k = A001221(n) and ik = A061395(n).at n=60A242421
• Number of von Neumann regular elements in the ring of 2 X 2 matrices over Z_n.at n=27A295071
• Smallest nonnegative number k such that k can be written in exactly n ways as x^2 + xy + y^2 where x and y are positive integers, with x >= y.at n=7A300419
• Smallest k such that circle centered at the origin and with radius sqrt(k) passes through exactly 6*n integer points in the hexagonal lattice (see A004016).at n=14A343771
• Numbers of the form (q1^b1)(q2^b2)(q3^b3)(q4^b4)(q5^b5)... where q1=7, q2=13, q3=19, q4=31, q5=37, ... (A002476) and b1>=b2>=b3>=b4>=b5...at n=20A344473
• a(n) is the smallest nonnegative integer k where exactly n ordered pairs of positive integers (x, y) exist such that x^2 + x*y + y^2 = k.at n=14A374090
• a(n) is the smallest nonnegative integer k where there are exactly n solutions to x^2 + x*y + y^2 = k with 0 < x < y.at n=7A374094