21283

Properties

Appears in sequences

• Discriminants of imaginary quadratic fields with class number 19 (negated).at n=38A046016
• Triangle read by rows: T(n,k) is the number of isomorphism classes of commutative semigroups of order n with k idempotents.at n=32A058116
• Primes which are the sum of three positive 4th powers.at n=30A085318
• prime(k) for those k where floor((2*(prime(k+1)-prime(k))*PrimePi(k) mod (8*k))/k) = m with m = 8.at n=38A109562
• Primes p such that q-p = 30, where q is the next prime after p.at n=23A124596
• Primes p of the form a^4+b^4+c^4 with a,b,c>=1 such that a^2+b^2+c^2 is another prime < p.at n=23A126117
• Prime numbers that are the sum of three distinct positive fourth powers.at n=18A126657
• Number of ordered triples (w,x,y) with all terms in {1,...,n} and 2w^2<=x^2+y^2.at n=33A211806
• Primes p such that p^4 + p - 1, p^4 + p^2 - 1, p^4 + p^3 - 1 are also prime.at n=5A226938
• Lexicographically largest increasing sequence of primes for which the continued square root map (see A257574) produces the decimal expansion of e (Euler's number).at n=26A257764
• Smallest prime that is the (sum, k*prime(k),k=m,..n+m-1) for some m, or 0 if no such m exists.at n=18A268467
• Numbers that are the sum of eight fourth powers in nine or more ways.at n=19A345584
• Numbers that are the sum of eight fourth powers in ten or more ways.at n=8A345585
• Numbers that are the sum of eight fourth powers in exactly ten ways.at n=6A345842
• Primes p_1 where products m of k = 5 consecutive primes p_1..p_k are such that only p_1 < m^(1/k).at n=24A376136
• Prime numbersat n=2391