51875

Appears in sequences

• Numbers k such that 13*2^k - 1 is prime.at n=14A001773
• Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 25 ones.at n=33A031793
• Coefficients of a polynomial used in calculation of A055915.at n=9A055918
• Antidiagonal sums of square array A082011.at n=24A082014
• Sum of next a(n) > 1 triangular numbers is a triangular number.at n=3A214648
• Smallest odd number greater than any previous term such that it divides the concatenation of all the previous terms and itself; begin with 1.at n=20A228806
• a(n)/144 is the maximum squared volume of a tetrahedron with the sum of its integer edge lengths equal to n.at n=24A371073
• a(n) = Sum_{j=1..n} Sum_{k=1..n} phi(2*j*k) / phi(k).at n=42A372664