55209

Appears in sequences

• a(n) = (10n+1)*(10n+9).at n=23A001535
• Schroeder pseudoprimes: Composites k that divide the k-th Schroeder number A001003(k-1).at n=34A075764
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 427", based on the 5-celled von Neumann neighborhood.at n=41A271904
• Number of 4-cycles in the n-triangular honeycomb queen graph.at n=13A289705