893952

Appears in sequences

• a(n) is the number of invertible 2 X 2 upper triangular matrices over Z_p where p = prime(n).at n=24A270775
• Decimal representation of the x-axis, from the origin to the right edge, of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 197", based on the 5-celled von Neumann neighborhood.at n=20A279755