42869

Appears in sequences

• Numbers k such that 27*2^k-1 is prime.at n=42A050539
• Composite and every divisor (except 1) contains the digit 6.at n=10A062674
• Golden semiprimes: a(n)=p*q and abs(p*phi-q)<1, where phi = golden ratio = (1+sqrt(5))/2.at n=17A108540
• Number of permutations of length n which avoid the patterns 2431, 4123, 4231.at n=9A116819
• Numbers n with following property: let c = nearest cube to n that is different from n and let p = nearest prime to n that is different from n. Then |n-c| = |n-p|.at n=33A163497
• Composite numbers and 1 which yield a prime whenever a 3 is inserted anywhere in them (including at the beginning or end).at n=40A216166
• Breadth-first reading of the subtree rooted at 7 of the tree where each parent node is the arithmetic derivative (A003415) of all its children.at n=42A327977