-2175

Appears in sequences

• a(n)=-a(n-1)+3*a(n-2), n>1 ; a(0)=1, a(1)=-3 .at n=9A152167
• First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 197", based on the 5-celled von Neumann neighborhood.at n=27A270719