-2115

Appears in sequences

• Lucas and Lehmer numbers with parameters (1 +- sqrt(-7))/2.at n=24A107920
• a(n) = (-1)^n*n*(n-2).at n=46A131386
• Row sums of the Riordan array (1-4x+4x^2, x(1-2x)) (A167431).at n=21A167433
• a(0)=1, a(1)=1; thereafter a(n) = -a(n-1) - 2*a(n-2).at n=22A169998
• a(n) = 5*a(n-1) - 8*a(n-2), with a(0)=0, a(1)=1.at n=8A190969
• Alternating sum of 12-gonal (or dodecagonal) numbers.at n=29A266088
• First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 371", based on the 5-celled von Neumann neighborhood.at n=27A271457