30689

Properties

Appears in sequences

• Numbers k such that 6!*(2*k-7)!/(k!*(k-1)!) is an integer.at n=33A004786
• Numbers k such that 7!*(2k-8)!/(k!*(k-1)!) is an integer.at n=37A004787
• Primes that remain prime through 3 iterations of function f(x) = 8x + 7.at n=15A023294
• Integer part of log(n^n)^(1 + log(log(1 + n))).at n=29A062479
• Numbers k such that (3^k + 7^k)/10 is prime.at n=7A128067
• Primes p=u^2+v^2 such that p+u or p+v is the next prime after p.at n=29A213996
• Primes of the form x^3 + 2*y^3, with nonnegative x and y.at n=40A219559
• Primes with distinct digits: a(n) is the least prime > a(n-1) such that a(n-1) and a(n) share no common digit.at n=24A250173
• Euclid-Mullin sequence (A000945) with initial value a(1) = 139 instead of a(1) = 2.at n=24A261703
• Primes whose base-6 representation is a square when read in base 10.at n=12A267820
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 793", based on the 5-celled von Neumann neighborhood.at n=31A273566
• Primes p that remain prime through 3 iterations of function f(x) = 6x - 1.at n=30A289109
• Primorial base emirps: prime numbers whose primorial base reversal is a different prime.at n=34A333425
• Number of regions formed when n points are placed in general position on each edge of a square and a chord is drawn from each point to the 3*n points on the other three sides.at n=8A392172
• Array read by antidiagonals: Place k points in general position on each side of a regular n-gon and join every pair of the k*n boundary points by a chord; T(n,k) (n >= 3, k >= 0) gives the number of regions in the resulting planar graph.at n=46A392228
• Prime numbersat n=3310