20811

Appears in sequences

• a(n) = a(n-1) + a(n-9) for n >= 9; a(n) = 1 for n=0..7; a(8) = 2.at n=55A005711
• Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 96.at n=25A031594
• Indices of primes in sequence defined by A(0) = 61, A(n) = 10*A(n-1) - 9 for n > 0.at n=24A101517
• Riordan array ( (1/(1-x))^m , x*A000108(x) ), m =4.at n=56A185945
• a(n) = number of steps to reach 0 when starting from k = (n^3)-1 and repeatedly applying the map that replaces k with k - A055401(k), where A055401(k) = the number of positive cubes needed to sum to k using the greedy algorithm.at n=55A261228
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 913", based on the 5-celled von Neumann neighborhood.at n=24A273768
• Number of n X 3 0..1 arrays with each 1 adjacent to 1, 3 or 5 king-move neighboring 1s.at n=7A296947
• T(n,k)=Number of nXk 0..1 arrays with each 1 adjacent to 1, 3 or 5 king-move neighboring 1s.at n=47A296952
• T(n,k)=Number of nXk 0..1 arrays with each 1 adjacent to 1, 3 or 5 king-move neighboring 1s.at n=52A296952
• Numbers k such that k and k + 1 are both Niven numbers in base 3/2 (A342426).at n=37A342427
• a(n) = Sum_{k=0..floor(n/3)} binomial(3*n-8*k-1,k).at n=19A373655
• Expansion of 1/(1 - x * (1 + x^4)^2).at n=28A373706