21427

Appears in sequences

• a(n) = ceiling(n*phi^17), where phi is the golden ratio, A001622.at n=6A004972
• Numbers n such that 8*10^n + 2*R_n + 1 is prime, where R_n = 11...1 is the repunit (A002275) of length n.at n=20A103075
• Number of different forests of unrooted trees, without isolated vertices, on n labeled nodes.at n=6A105784
• Numerators of partial sums of a series for the inverse of the arithmetic-geometric mean (agM) of 1/2 and 1.at n=3A130037
• Total sum of parts of multiplicity 5 in all partitions of n.at n=38A222733
• Numbers n such that n!3 + 3^3 is prime.at n=35A247886
• Number of (n+2) X (2+2) 0..3 arrays with every 3 X 3 subblock row and diagonal sum equal to 2 3 4 6 or 7 and every 3 X 3 column and antidiagonal sum not equal to 2 3 4 6 or 7.at n=7A252401
• Result of inserting the integers n = 0, 1, 2, ... in this order into an initially empty list, where n is inserted between the pair of consecutive elements with sum equal to n and minimal absolute difference, or at the end of the list if no such pair exists.at n=20A360447