21036

Appears in sequences

• Numbers n such that (n + prime(n)), (n+1 + prime(n+1)), (n+2 + prime(n+2)) and (n+3 + prime(n+3)) are divisible by 5.at n=14A107582
• Number of permutations of length n which avoid the patterns 2431, 3124, 3421.at n=9A116778
• a(n) = floor((Pi^2/6)^n).at n=20A125892
• Triangle W, read by rows, where column k of W = column 0 of W^(k+1) for k>=0 such that W equals the matrix cube of P = A136220 with column 0 of W = column 0 of P shift up one row.at n=23A136231
• Matrix cube of triangle W = A136231; also equals P^9, where P = triangle A136220.at n=10A136238
• Number of 2n X 2 0..2 arrays with values 0..2 introduced in row major order and each element equal to an odd number of horizontal and vertical neighbors.at n=5A198474
• T(n,k)=Number of 2nX2k 0..2 arrays with values 0..2 introduced in row major order and each element equal to an odd number of horizontal and vertical neighbors.at n=15A198477
• T(n,k)=Number of 2nX2k 0..2 arrays with values 0..2 introduced in row major order and each element equal to an odd number of horizontal and vertical neighbors.at n=20A198477
• T(n,k)=Number of 2nX2k 0..2 arrays with values 0..2 introduced in row major order and each element equal to exactly one horizontal or vertical neighbor.at n=15A198532
• T(n,k)=Number of 2nX2k 0..2 arrays with values 0..2 introduced in row major order and each element equal to exactly one horizontal or vertical neighbor.at n=20A198532
• Coefficients of mock modular form H_2^(7) of type 1A, divided by 4.at n=32A256057
• Number of length 3 1..(n+1) arrays with every leading partial sum divisible by 2, 3, 5 or 7.at n=34A258634
• G.f.: Sum_{n>=0} log(1 + Sum_{k>=1} k^n * 2^(n*k) * x^k )^n / n!, a power series in x with integer coefficients.at n=4A277035
• Triangle read by rows: T(n,k) = number of times the value k appears on the parking functions of length n.at n=16A298593
• Positions of records in A366091.at n=52A366065
• Number of edges in a graph of n adjacent rectangles in a row with all possible diagonals drawn, as in A306302, but without the rectangles' edges which are perpendicular to the row.at n=15A369177