19730

Appears in sequences

• Numbers n such that 123*2^n-1 is prime.at n=30A050587
• Numbers n such that 2*10^n + 6*R_n + 3 is prime, where R_n = 11...1 is the repunit (A002275) of length n.at n=19A102957
• G.f.: Product_{n>=1} (1 + A002203(n)*x^n + (-1)^n*x^(2*n)) where A002203 is the companion Pell numbers.at n=9A204275
• Number of (n+1) X 4 0..2 arrays with every 2 X 2 subblock having nonzero determinant and commuting with every horizontal or vertical neighbor.at n=16A207144
• Number of (n+1) X 6 0..2 arrays with every 2 X 2 subblock having nonzero determinant and commuting with every horizontal or vertical neighbor.at n=14A207146
• Number of (n+1) X 8 0..2 arrays with every 2 X 2 subblock having nonzero determinant and commuting with every horizontal or vertical neighbor.at n=12A207148
• Number of permutations of [n] whose lengths of increasing runs are squares.at n=10A317129
• a(n) is the number of vertices formed by n-secting the angles of a decagon.at n=30A335801
• First differences of A307632.at n=17A348773
• a(n) = A348773(2*n).at n=8A348775