27877

Appears in sequences

• Numbers k such that 6!*(2*k-7)!/(k!*(k-1)!) is an integer.at n=29A004786
• Numbers k such that 7!*(2k-8)!/(k!*(k-1)!) is an integer.at n=33A004787
• Numbers k such that the continued fraction for sqrt(k) has period 77.at n=30A020416
• Expansion of 1/sqrt((1-x)^2 - 4*x^4).at n=18A098482
• Number of permutations of length n which avoid the patterns 1342, 2341, 4132; or avoid the patterns 2431, 3124, 4231.at n=9A116742
• Numbers k such that k and k^2 use only the digits 1, 2, 7, 8 and 9.at n=13A137018
• Number of reduced words of length n in the Weyl group D_9.at n=10A162212
• Triangle read by rows: T(n,k) is the number of secondary structures of size n having k stacks of length 2 (n>=0, k>=0).at n=45A202841
• Semiprimes generated by the polynomial 2 * n^2 + 29.at n=30A241554
• Number of (n+2) X (2+2) 0..1 arrays with each 3 X 3 subblock having clockwise perimeter pattern 00000001 00000011 or 00001111.at n=9A260364
• Composite numbers of the form 2*k^2 + 29.at n=30A352949
• Array read by antidiagonals: T(m,n) is the number of (non-null) connected induced subgraphs in the rook graph K_m X K_n.at n=23A360873
• Array read by antidiagonals: T(m,n) is the number of (non-null) connected induced subgraphs in the rook graph K_m X K_n.at n=25A360873
• Numerator of the least probability that a particular free polyomino with n cells appears in internal diffusion-limited aggregation on the square lattice.at n=10A368388
• One-third of the total number of edges formed after n points have been placed in general position on each edge of a triangle (as in A365929).at n=12A389626