28055

Appears in sequences

• Denominators of continued fraction convergents to sqrt(165).at n=9A041305
• Denominators of continued fraction convergents to sqrt(660).at n=9A042269
• a(n) = n^4 - 3*n^2 + 1.at n=13A057722
• A Chebyshev S-sequence with Diophantine property.at n=4A078362
• Fibonacci sequence beginning 12, 67.at n=14A091074
• Triangle read by rows: T(n,k) is the number of deco polyominoes of height n and such that the sum of the bottom levels of all columns is k (n>=1, k>=0; informally, the number of the "missing" cells in the right bottom corner of the polyomino). A deco polyomino is a directed column-convex polyomino in which the height, measured along the diagonal, is attained only in the last column.at n=48A122104
• Number of conjugacy classes for a non-abelian group of order p^3, where p is prime: a(n) = p^2 + p - 1 where p = prime(n).at n=38A319597
• a(n) is the largest k such that the sum of k consecutive reciprocals 1/p_n + ... + 1/p_(n+k-1) does not exceed 1 (where p_n = n-th prime).at n=25A327600