87840

Appears in sequences

• Glaisher's function G(n) (18 squares version).at n=19A002609
• a(n) = 7*a(n-1) - a(n-2) + 4, with a(0) = 0, a(1) = 5.at n=6A003482
• Theta series of A*_15 lattice.at n=79A023927
• a(n) = F(n)*F(n-1) if n odd otherwise F(n)*F(n-1)-1, where F = Fibonacci numbers A000045.at n=13A059840
• a(n) = F(3)*F(n)*F(n+1) + F(4)*F(n+1)^2 - F(4) if n even, F(3)*F(n)*F(n+1) + F(4)*F(n+1)^2 if n odd, where F(n) is the n-th Fibonacci number (A000045).at n=11A080143
• Positive values of k such that there is exactly one permutation p of (1,2,3,...,k) such that i+p(i) is a Fibonacci number for 1<=i<=k.at n=23A097083
• Partial sums of Chebyshev sequence S(n,17)= U(n,17/2)=A078366(n).at n=4A097831
• Triangle read by rows: T(n,k) is number of paths from (0,0) to (3n,0) that stay in the first quadrant (but may touch the horizontal axis), consisting of steps u=(2,1),U=(1,2), or d=(1,-1) and have k hills (a hill is either a ud or a Udd starting at the x-axis).at n=29A108431
• Numerator of Sum_{k=1..n} 1/(Fibonacci(k)*Fibonacci(k+2)).at n=11A119996
• Number of n X 1 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,0,1,3,4 for x=0,1,2,3,4.at n=24A195971
• a(n) = F(n)^2 - F(n-1)^2 or F(n+1) * F(n-2) where F(n) = A000045(n), the Fibonacci numbers.at n=13A226205
• a(n) = a(n-1) + a(n-2) + a(n-3), with a(0) = a(1) = 1, a(2) = 0.at n=27A236165
• Number of terms in the cycle index Z(S_n X S_n) of the Cartesian product of the symmetric group S_n with itself that contain q cycles, where 1 <= q <= n*n. (Triangular array.)at n=58A279514