20834

Appears in sequences

• Number of paraffins.at n=43A005998
• a(n) = Sum_{i=1..n} Sum_{j=1..i} (prime(i)^2 - prime(j)^2).at n=10A062021
• Duplicate of A132186.at n=5A086907
• Number of idempotent n X n matrices over GF(2); also number of diagonalizable n X n matrices over GF(2).at n=5A132186
• Sum of first n terms divides the concatenation of the first n terms.at n=13A166064
• Number of nX5 0..4 arrays with each element equal to the number its horizontal and vertical neighbors unequal to itself.at n=14A195959
• Relative of Hofstadter Q-sequence: a(n) = max(0, n+20830) for n <= 0; a(n) = a(n-a(n-1)) + a(n-a(n-2)) + a(n-a(n-3)) for n > 0.at n=5A283887
• Relative of Hofstadter Q-sequence: a(n) = max(0, n+20830) for n <= 0; a(n) = a(n-a(n-1)) + a(n-a(n-2)) + a(n-a(n-3)) for n > 0.at n=38A283887
• Triangular array read by rows. T(n,k) is the number of n X n matrices over GF(2) such that the sum of the dimensions of their eigenspaces taken over all eigenvalues is k, 0 <= k <= n, n >= 0.at n=20A346201
• Triangular array read by rows. T(n,k) is the number of n X n matrices over GF(2) that can be decomposed as the direct sum of k cyclic matrices, 0<=k<=n, n>=0.at n=20A346677