251721

Appears in sequences

• Numbers k such that prime(k) == 5 (mod k).at n=11A023147
• Values of transition of A072608(n) from alternating behavior (0,1,0,1,..) into steadily-1 (1,1,1,..) behavior or changing back. Expressing in terms of A072609(n): at n values it switches from steadily 0 into steadily 1 successive values or back.at n=23A072610
• Number of solutions to x*frac[p(x)/x]<=Log[n] or A004648(n)<=Log[n].at n=42A099641
• Numbers n such that either prime(n-1) == -1 (mod n) or prime(n+1) == -1 (mod n) but not both.at n=35A225318
• First point of the straight lines in A340649.at n=6A343496
• Indices of records in A366092.at n=24A366093