31686

Appears in sequences

• a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (1, p(1), p(2), ...), t = (composite numbers).at n=43A025100
• Becomes prime or 4 after exactly 9 iterations of f(x) = sum of prime factors of x.at n=27A048131
• Assume the conjectured terms of A105594 are the correct beginnings of the trajectories described in A003508. a(n) is a record length of b(n) iterations to arrive at the collected trajectories. This sequence cites the a(n)'s.at n=19A105600
• G.f.: A(x) = Sum_{n>=0} x^n / Product_{k=1..n} (1 - k*x^k).at n=20A193196
• Linear recurrence sequence with infrequent pseudoprimes, a(n) = -a(n-1) + a(n-2) - a(n-3) + a(n-5), with initial terms (5, -1, 3, -7, 11).at n=18A225984