23741

Properties

Appears in sequences

• Numbers k such that the continued fraction for sqrt(k) has period 55.at n=33A020394
• Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted the two central terms are both 61.at n=0A031649
• Recursive prime generating sequence.at n=61A039726
• Initial term in sequence of four consecutive primes separated by 3 consecutive differences each <= 6 (i.e., when d = 2, 4 or 6) and forming pattern = [2, 4, 6]; short notation = [246] d-pattern.at n=27A078847
• Fifth column of triangle A115193 (called C(1,2)).at n=5A115202
• Primes p such that (p, p+2, p+6, p+12) is a prime quadruple.at n=35A172454
• Primes p such that the polynomial x^2 + x + p generates only primes for x = 0, ..., 4.at n=18A187057
• Initial primes of 5 consecutive primes with consecutive gaps 2, 4, 6, 8.at n=6A190814
• Prime numbers p such that x^2 + x + p produces primes for x = 0..4 but not x = 5.at n=10A210363
• Smallest prime p such that n primes exist between the prime triple (p, p+2, p+6) and the next prime triple.at n=41A214450
• Primes p such that p+2 and q are primes, where q is concatenation of binary representations of p and p+2: q = p * 2^L + p+2, where L is the length of binary representation of p+2: L=A070939(p+2).at n=33A232238
• Primes p such that f(f(p)) is prime, where f(x) = x^4 + x^3 + x^2 + x + 1 = A053699(x).at n=26A237445
• Prime time primes (of the form HMMSS with primes H < 24 and MM, SS < 60) such that the corresponding number of seconds after midnight is also prime.at n=26A295000
• Triangle read by rows: T(m,n) is the label of the largest square that an (m,n)-leaper (a generalization of a chess knight) reaches before it can no longer move, starting on a board with squares spirally numbered, starting at 1; 1 <= n < m. Each move is to the lowest-numbered unvisited square.at n=34A306197
• Primes of the form k^2 + 25.at n=36A346145
• G.f. A(x) satisfies: A(x) = 1 / (1 - x + x^4 * A(x)).at n=23A349048
• Number of n-digit numbers whose sum of digits is a prime.at n=4A372897
• Primes p such that p + 6, p + 12, p + 20, p + 26 and p + 32 are also primes.at n=13A384769
• Prime numbersat n=2639