21084

Appears in sequences

• Convolution of Fibonacci F(n+1), n>=0, with F(n+8), n>=0.at n=10A067431
• Number of almost base-2 palindromic primes (A095743) in range ]2^n,2^(n+1)].at n=27A095753
• a(n) = 2*n*(6*n-1).at n=42A126964
• 2^(2p-2) modulo p^3 for p=odd primes.at n=8A216160
• (-1)^((p-1)/2)*Binomial(p-1,(p-1)/2) mod p^3 where p is the n-th prime.at n=8A224807
• Number of paths from (0,0,0) to (n,n,n) avoiding 3 or more consecutive right steps, 3 or more consecutive up steps, and 3 or more consecutive away steps.at n=4A247150
• a(n) = ( 2*n*(2*n^2 + 11*n + 26) - (-1)^n + 1 )/16.at n=42A256666
• Expansion of Product_{k>=1} (1 + x^prime(k))/(1 - x^prime(k)).at n=54A300413
• Number of nX3 0..1 arrays with every element equal to 0, 2, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.at n=8A300534
• T(n,k)=Number of nXk 0..1 arrays with every element equal to 0, 2, 3 or 4 horizontally, vertically or antidiagonally adjacent elements, with upper left element zero.at n=57A300539
• a(n) = 54*n^2 - 26*n + 4 (n>=1).at n=19A304381
• Take apart the sides of each of the integer-sided triangles with perimeter n (at their vertices) and rearrange them orthogonally in 3-space so that their endpoints coincide at a single point. a(n) is the total volume of all rectangular prisms enclosed in this way.at n=31A308233
• Triangle read by rows: T(n,k) = arithmetic derivative of (1 + A002110(n) + A002110(k)), 1 <= k <= n, where A002110(n) is the n-th primorial number.at n=15A373845
• Expansion of 1/sqrt((1-2*x)^3 * (1-6*x)).at n=6A383950