-2680

Appears in sequences

• Alternating sum of 9-gonal (or nonagonal) numbers.at n=39A266086
• First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 179", based on the 5-celled von Neumann neighborhood.at n=31A270625
• Hurwitz inverse of partition numbers A000041.at n=8A302199