22454

Appears in sequences

• Number of 2-trees rooted at an asymmetric end-edge.at n=8A063682
• a(n) = Sum_{k=1..n} sigma(k)*2^(n-k) where sigma(k) = A000203(k) is the sum of divisors of k.at n=12A066767
• Consider trajectory of n under repeated applications of the function f(x) = 'Sum of the prime factors of x (with multiplicity)' (see A029908). Sequence gives composite numbers n that end at a prime m that divides n and m is greater than any m's seen already.at n=10A084931
• a(n) = numerator of constant lambda(n) involved in a recurrence for the Atkin polynomials A_k(j).at n=17A145226
• Squarefree numbers k such that the sum of the distinct prime factors of k is twice the difference between the largest and the smallest prime factors of k.at n=25A324210