22311

Appears in sequences

• Numbers whose base-7 representation contains exactly four 2's.at n=34A043404
• Numbers n such that h(n) = 3 h(n-1) where h(n) is the length of the sequence {n, f(n), f(f(n)), ...., 1} in the Collatz (or 3x + 1) problem. (The earliest "1" is meant.)at n=22A078420
• Numbers of the form 110 + p^2. (where p is a prime).at n=34A138693
• The number of 54321-avoiding separable permutations of length n.at n=9A165522
• Numbers k such that s(k) = s(k+1) but phi(k) != phi(k+1), where s(k) = phi(k) + phi(phi(k)) + ... + 1 is the sum of iterated phi (A092693).at n=13A291177
• Numbers n such that there are precisely 14 groups of orders n and n + 1.at n=1A298431
• G.f. A(x) satisfies: A(x) = Product_{k>=1} (1 + k*x^k*A(x)^k).at n=8A301578
• Expansion of Product_{i>=1, j>=1, k>=1} (1 + x^(i*j*k))^(i*j*k).at n=11A318414
• Numbers k such that A075255(k) is the square of a prime.at n=19A386954