27143

Properties

Appears in sequences

• Primes that remain prime through 3 iterations of function f(x) = 5x + 4.at n=36A023284
• Primes that remain prime through 4 iterations of function f(x) = 5x + 4.at n=9A023314
• Smallest primes whose residue modulo its difference from the next prime is 2n-1.at n=17A060235
• Smallest prime p of two consecutive primes, p < q, such that gcd(p+1, q+1) = 2n.at n=17A067604
• Numbers k where the root mean square (RMS) of k and 7 is an integer, i.e., sqrt((k^2 + 7^2)/2) is an integer.at n=15A076293
• Denominators of convergents of the continued fraction with the n+1 partial quotients: [2;2,2,...(n 2's)...,2,n+1], starting with [1], [2;2], [2;2,3], [2;2,2,4], ...at n=10A088211
• Primes of the form 2*n^2 + 2*n - 1.at n=37A098828
• Largest of six consecutive primes the sum of the digits of each of which is prime.at n=20A106720
• Largest of seven consecutive primes whose sum of digits is prime.at n=9A106721
• Largest of eight consecutive primes whose sum of digits is prime.at n=4A106724
• prime(k) for those k where floor((2*(prime(k+1)-prime(k))*PrimePi(k) mod (8*k))/k) = m with m = 10.at n=29A109564
• Primes p such that q-p = 36, where q is the next prime after p.at n=9A134117
• Primes of the form (p^2 - 3)/2 where p is also prime.at n=24A165635
• Noncomposite numbers in the southern ray of the Ulam spiral as oriented on the March 1964 cover of Scientific American.at n=22A168027
• Part of the positive proper solutions x of the Pell equation x^2 - 2*y^2 = - 7^2 based on the fundamental solution (x0, y0)= (1, 5).at n=5A254758
• Solution of the complementary equation a(n) = 2*a(n-1) - a(n-2) + b(n-1) + n, where a(0) = 1, a(1) = 2, b(0) = 3, and (a(n)) and (b(n)) are increasing complementary sequences.at n=41A294872
• Number of partitions of n with eight parts in which no part occurs more than twice.at n=43A320596
• Primes having square prime gaps to both neighbor primes.at n=4A353088
• First of three consecutive primes p,q,r such that p+q, p+r and q+r are all triprimes.at n=11A362203
• For a line L in the plane, let C(L) denote the number of prime points [k, prime(k)] on L, and let M(L) denote the maximum prime(k) for any of these points; a(n) = minimum M(L) over all lines with C(L) = n, or -1 if there is no such line.at n=40A376187