20820

Appears in sequences

• Number of mobiles (circular rooted trees) with n nodes and 3 leaves.at n=29A055341
• Integer part of square root of n-th Fibonacci number.at n=43A061287
• Numbers k such that phi(k)+sigma(k) is a perfect cube.at n=14A061366
• a(n) = floor(11^n/7^n).at n=22A094993
• Numbers such that the digital sum base 2 and the digital sum base 3 and the digital sum base 4 all are equal.at n=6A135122
• Position of first occurrence of n in A182576.at n=19A182580
• Number of isomorphism classes of nanocones with 3 pentagons and a nearsymmetric boundary of length n.at n=38A198014
• Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 2 4 6 or 7.at n=7A252450
• T(n,k)=Number of (n+2)X(k+2) 0..3 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 2 4 6 or 7.at n=28A252457
• T(n,k)=Number of (n+2)X(k+2) 0..3 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 2 4 6 or 7.at n=35A252457
• Expansion of Product_{k>=1} 1/(1-x^(k+8))^k.at n=49A263364
• a(n) = 10^(prime(n)-1) mod prime(n)^2.at n=42A265012
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 737", based on the 5-celled von Neumann neighborhood.at n=24A273480
• Nonprime numbers k such that k divides sigma(k^2) - 1.at n=11A283744
• Expansion of e.g.f. log(1-x) * tan(log(1-x)/2).at n=8A357594
• Sum of all prime encoded perfect partitions of n.at n=14A360713