21284

Appears in sequences

• Numbers k such that 157*2^k+1 is prime.at n=15A032455
• Binomial transform of A066247 (characteristic function of composite numbers).at n=15A143962
• Number of binary strings of length n with no substrings equal to 0001, 0110, or 0111.at n=28A164476
• Number of -n..n arrays x(0..3) of 4 elements with zero sum and no element more than one greater than the previous.at n=42A199848
• Numbers generated by a Fibonacci-like sequence in which zeros are suppressed.at n=36A243063
• Numbers n such that the decimal number concat(5,n) is a square.at n=34A273360
• Triangle read by rows: T(n,m) (n >= m >= 1) = number of edges in the graph formed by drawing the line segments connecting any two of the (n+1) X (m+1) lattice points in an n X m grid of squares.at n=14A333278
• Numbers m such that m = p^2 + k^2, with p > 0, where p = A007954(m) = the product of digits of m.at n=22A334557