31261

Appears in sequences

• E.g.f.: exp(x)/(1+LambertW(x)).at n=6A069856
• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, -1), (-1, -1, 1), (-1, 1, 0), (0, 1, -1), (1, 0, 0)}.at n=12A148017
• Numbers k that are the products of two distinct primes such that 2*k-1, 4*k-3, 8*k-7, 16*k-15, 32*k-31 and 64*k-63 are also products of two distinct primes.at n=18A177215
• Numbers k that are the products of two distinct primes such that 2*k-1, 4*k-3, 8*k-7, 16*k-15, 32*k-31, 64*k-63 and 128*k-127 are also products of two distinct primes.at n=3A177216
• The products k of two distinct primes such that 2*k-1, 4*k-3, 8*k-7, 16*k-15, 32*k-31, 64*k-63, 128*k-127 and 256*k-255 are also products of two distinct primes.at n=0A177217
• Smallest numbers with properties: products of two distinct primes of the form a(k)=2^n*m-(2^n-1), n:0->k.at n=8A177220
• Smallest numbers with properties: products of two distinct primes of the form a(k)=2^n*m-(2^n-1), n:0->k.at n=9A177220
• Number of nondecreasing -n..n vectors of length 5 whose dot product with some nondecreasing -n..n vector equals 5.at n=8A226413
• MM-numbers of crossing set partitions.at n=37A324324
• Number T(n,k) of endofunctions on [n] with exactly k isolated fixed points; triangle T(n,k), n >= 0, 0 <= k <= n, read by rows.at n=21A350212
• Square array T(n,k), n >= 0, k >= 0, read by antidiagonals downwards, where T(n,k) = (-1)^n * Sum_{j=0..n} (-k*j)^j * binomial(n,j).at n=34A362019
• Square array T(n,k), n >= 0, k >= 0, read by antidiagonals downwards, where T(n,k) = Sum_{j=0..n} (-k)^(n-j) * j^j * binomial(n,j).at n=34A362856
• Zeroless analog of tribonacci numbers.at n=49A371911