25603

Properties

Appears in sequences

• Positive numbers k such that k and 2*k are anagrams in base 9 (written in base 9).at n=35A023079
• Primes of the form k^2 + 3.at n=27A049423
• Primes p from A031924 such that A052180(primepi(p)) = 29.at n=14A052236
• Duplicate of A049423.at n=27A121825
• Base 10 numbers d_1 d_2 ... d_k such that the digits d_i are distinct, and Sum_{i=1..k-1} d_i^i = d_k^k.at n=8A177772
• Number of distinct solutions of sum{i=1..6}(x(2i-1)*x(2i)) = 1 (mod n), with x() only in 2..n-2.at n=8A180829
• Integers k such that 2^(k-1) == 1 (mod k) and 2^(m-1) == 1 (mod m), where m = k*(A000265(k-1) - 1) + 1 and A000265 gives the odd part of its argument.at n=16A187849
• List of prime factors of 10^(10^(10^100)) - 10.at n=37A227246
• Sixth prime p such that (p+n)^2+n is prime but (p+j)^2+j is not prime for all 0<j<n.at n=22A238678
• P(n,k) is an array read by rows, with n > 0 and k=1..5, where row n gives the chain of 5 consecutive primes {p(i), p(i+1), p(i+2), p(i+3), p(i+4)} having the symmetrical property p(i) + p(i+4) = p(i+1) + p(i+3) = 2*p(i+2) for some index i.at n=5A267028
• The first prime of 8 consecutive primes a, b, c, d, e, f, g, h such that a + g = c + e and b + h = d + f.at n=23A292618
• Pseudo-safe-primes: numbers n = 2m+1 with 2^m congruent to n+1 or 3n-1 modulo m*n, but m composite.at n=5A300193
• a(n) is the least prime p such that 2-adic valuation of p-3 is n.at n=10A318207
• Numbers that are the sum of eight fourth powers in exactly ten ways.at n=23A345842
• Prime numbersat n=2820