20824

Appears in sequences

• Coordination sequence for net formed by holes in D_4 lattice.at n=12A010079
• Number of fixed polyominoes with n cells of which no four are equally spaced on a straight line.at n=13A065068
• Numbers k such that (k+1)*phi(k) is a perfect square.at n=20A069952
• Structured octagonal anti-prism numbers.at n=18A100184
• Imaginary part of absolute Gaussian perfect numbers, in order of increasing magnitude.at n=29A102532
• a(n+2) = 3*a(n+1) + a(n), with a(0) = 1, a(1) = 5.at n=8A108300
• Triangle read by rows: T(n,m) is the number of cyclic permutations of [n] in which m of successive numbers add to a prime. 0<=m<=n, read by rows n>=0.at n=61A132178
• Eigentriangle by rows, A143971 * (A108300 * 0^(n-k)); 1<=k<=1.at n=54A143972
• Sum of parts of the n-th subsection of the head of the last section of the set of partitions of any odd integer >= 2n+1.at n=15A182995
• Fifth-order spt function.at n=11A221143
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 901", based on the 5-celled von Neumann neighborhood.at n=24A273744
• a(n) = 17*n^2 - 1.at n=35A321180
• Starts of runs of 3 consecutive positive negaFibonacci-Niven numbers (A331085).at n=41A331087
• Number of multiplex juggling cards with n balls and capacity 2.at n=13A370304
• Integers k such that k*2^k + 3 is prime.at n=17A382094