171955

Appears in sequences

• a(0) = 0, a(1) = 1 and for n >= 2, a(n) = floor(sqrt(2 * (a(n-2)^2 + a(n-1)^2))).at n=26A093332
• a(n) = floor(log(A111288(n))).at n=36A111388
• A triangular sequence of the expansion of: (1-Prime[n])^n: t(n,m)=(-1)^m*Prime[n]^(n - m)*Binomial[n, m]; with Prime[0]=1 defined to extend and lower the results.at n=32A141028
• Number of (n+1) X (n+1) -9..9 symmetric matrices with every 2 X 2 subblock having sum zero and one or two distinct values.at n=19A211549
• Number of (w,x,y,z) with all terms in {0,...,n}, and w, x and y odd.at n=34A212763